There should be an easy-to-find chart with pressure, temp, gas line size, length, etc. floating around the internet.
You can store your gas either outside your kegerator, or inside, but be aware that if you put it inside your cooling unit, the CO2 inside will become denser, and therefore the pressure gauge will read a little lower. This does not mean that there is a sudden loss of gas, only that the CO2 is denser and therefore has less volume and less pressure than warmer CO2.
You can charge your beer a couple of ways:
Set it to proper pressure (about 10-12 lbs. usually) and leave it for a couple of weeks (what I would do if not in a hurry) or set pressure to like 30 lbs and roll the keg around to mix the CO2 into solution in a hurry. You'll probably still want to let it sit at proper pressure for a couple of days to settle, but it can go MUCH faster this way. But you also run the risk of over carbing your beer accidentally.
Also you CAN add priming sugar to your keg and leave it sit off the gas to carb naturally. Some people do this. I don't. it will create a bit more sediment, but it will allow you to provide a natural carb and not use as much CO2 from the store. Then you only use the CO2 tank to top off as your pour from the keg.