Ok, so you are young, just getting started on your own, and want to prepare for... something.
As others have said, what is it you are preparing for?
Although the Zombie Apocalypse and TEOTWAWKI are at the top of a lot of people's minds, the reality is that the things you really need to be prepared for are going to be much more mundane. Things like job loss, robbery, fire, flood, the weather, and other things you never though of on a random Tuesday afternoon.
The whole thing about being prepared is, well, being prepared. It isn't about the gear (although it has its place) it is about being ready for what life decides to throw at you.
Events are rarely well defined situations that you could have planned for. Since every situation is different and probably changing by the minute your plan will have to change with it.
Keep in mind disasters aren't discrete events. They are a continuum with "Normal" at one end and dead at the other. You start at "Normal" and descend towards dead. Every step of the way it is your job to keep moving away from dead and towards "Normal".
Regardless of the scenario, the first things to go will be high level stuff like modern banking, communications, and electricity. Those will start to take out more important things like perishable food, known clean water, and transportation. That will start to take out even more basic things like access to food, access to medical care, shelter. That starts to take out personal security and finally life.
There is no guarantee that things will flow in such a predictable and linear manner. Any given event might hop around or start in the middle.
How do we plan for this stuff? What do we do when things go bad?
Truthfully, almost all plans I have seen for any event all go the same way... survive long enough for "the system" to come back and support you. There are very few that have planned for 100% self sufficiency... and in my opinion, it is unlikely that we will ever get to that point.
In most cases it is all about having enough resources to ride out the temporary disruption to life as we know it. If you lose a job it is about making it to the next job. If you lose power, it is about making it until the power comes back. If transportation is shut down, it is about waiting until it is working again.
If it looks like the situation will last longer than your ability to ride it out, you have to move to somewhere where resources are available to you.
The number one thing you can prepare is your mind. Bad things will happen and you can't go all to pieces in the middle of it. Simply having a plan (not necessarily the best one either) will go a long way in providing you with a sense of stability and control. It can let you pause, think, and make better decisions than you would make in full-on reaction mode. Learn. Never stop learning. The more you know the better prepared you are.
Figure out who your friends are and who they aren't. As others have said, it is really tough to go it alone. Knowing who you can call at 3:30am when the neighboring tenants just burned down your apartment building is important. This also has to go both ways. You have to be willing to help them out as well.
You say you don't have much money, that is Ok, we all have been there at one time or another. Like any other resource, you have a limited supply and need to use it efficiently. This is going to mean thinking. You should be building a reserve to carry you through a job loss or unexpected large expense. You should be planning how to get out of as much debt as you can. Live below your means at least for a while. You don't have to spend a lot of money on stuff to get yourself ahead of the curve. There are plenty of things you can do until you have the money for the more obvious items.
Gather your important documents together. Make copies. Copy both sides of everything in your wallet. Make sure you know the phone numbers and what you need to do to cancel your credit cards, obtain new IDs, change your address, access your bank accounts, etc. Stash a copy with a friend or some other secure place.
Never let your gas tank go below half full. It doesn't cost you anything more other than a little time at the pump, but you will know that you always have about 150 to 200 miles of range available if you need to get somewhere.
Check the air in your spare tire. Take a weekend afternoon and change one of your tires with what is in the car.
Stash a spare set of clothes and a towel in a bag in the car. Change them as appropriate for the seasons.
Get in shape. If you can't walk 5-10 miles unloaded, what is going to happen when you try to schlep around a 50 pound pack of stuff? You don't have to go to the gym, just start walking. When 5 mile walks are no problem start adding a pack.
Start looking at everything as a potential resource. Wander the aisles in stores. See what else they have. When things go bad and everyone has cleaned out the big stores, you will know that in the back corner of the forgotten mom and pop hardware store there is probably a can of alcohol or small propane cylinder that most have forgotten about.
Keep in mind that even if you don't have the item now, knowing where to find it might be enough.
Learn to look at your environment. Know where the rivers and streams are. Know where the low spots are and the high ground. Know what would make good shelter and learn to look for the choke points in travel. Think about what this all looks like covered in snow, or with the rivers over their banks, or with the roads packed with panicked people.
Starting to get the idea?
When you start to have some money for "stuff" start small.
Water and food: Buy a little extra to keep at least a few days supply around. Grow this slowly over time. You also have to actually use the stuff you are stockpiling so you don't find yourself with decade old soup when you need it. If you buy water in bottles fill empty spaces in the fridge and freezer with them. You can take them out when you need the space and the extra mass will help ride through power outages (so long as you don't open the door).
Pay attention to yard and garage sales for useful items. Camping gear can often be had for almost nothing. I gave $20 total for a pair of Coleman lanterns and a two burner stove. I paid $5 for an older two person tent. Watch for out of season sales at the sporting goods stores. You can sometimes get some deep discounts especially on the less sexy but really useful stuff like mess kits, bags, canteens, etc. After Halloween glow sticks are often in the discount bin for well under a dollar.
Keep in mind that a whole lot of "outdoors" stuff is quite trendy. If you are willing to have out of style slightly heavier equipment, you can cash in on the trailing edge of the trend.
Get a paper atlas of the US. Yes, paper. Learn to use it. When no one has seen a charged battery in days you will have the ability to navigate.
Take a first aid course. The first responder courses are good. Put together a good first aid kit.
Once you have a collection of gear designed around 48 hours of survival, go camping and test it. Start in the back yard if you want, but the goal should be to use only what you have in your kit. You will get to use some expired stuff and see what you didn't think of. Once this works in nice weather, try it again in rainy, windy, or cold weather.
The "Zombie Apocalypse" mentality might have been a good construct to get people to start thinking about the unexpected, but I think it has done a disservice to most people by causing them to either "prepare" for a scenario where the threat is made-up, lurching, infectious, targets for decked out AR-15s or to write the whole thing off as silly. They have no idea that the real threat they need to prepare for is hunger, exposure, and disease that follows a breakdown of the systems we have come to depend upon.