If you are lucky enough to be driving around from that car you got at the dealership, there is a good chance that you are not going to get far unless you can get a refill of gas. Even with a full tank, you can only to expect to drive for about 300 to 400 miles from where you started. You will need to find gas somewhere--here are a few things to consider when you happen to find yourself at an Arco gas station
Safety and Security
Most Arco gas stations are being upgraded which could be a good and a bad thing. Getting inside a secured Arco will require you to get through the reinforced windows. If you are already inside, the windows will help keep the undead out. If you are trying to figure out if there is any gas, you will need to ensure the emergency gas shut-off is disengaged (outside) then go back inside to activate the pumps before going back outside to actually pump gas--all while keeping the zombies at bay! Lastly, if you have to, when inside, you could get to the roof through the access ladder but you'll be backing yourself into a corner if you do that--remember, you still have to cut the lock on the ladder cover.
There are a few perishable goods at a gas station. If anything, the main things you will find will not be found anywhere on the food triangle of healthy food groups--also know as junk food. At this point, who's worrying about your diet, especially when there's hundreds of those things outside looking at you like you are a big walking side of beef?
Long Term Solution
From the managers station or the bathroom, there really isn't a good place to call home. I suppose you could stay in the crawl space but you will need to devise a way to be able to get to the roof without having to drop back into the first floor--in the event that the inside is overrun with those brainless walkers. Remember, this is a crawl space and that it may be a good place to get rest but you wouldn't want to get stuck in this space.
Who knows, you probably couldn't go far with a vehicle with all those cars, trucks, and whatever else that may have already broken down before you got on the road. You do run the risk of getting stuck on the road, so be careful what you drive and where you drive. Sometimes it would help if you know how to operate different types of vehicles. Look over there--it's a dirt bike--maybe I can get out of this area with that?