Don't do anything until you've scanned for codes. Not everything will set the CEL off (flashing or solid). Once you've retrieved codes then post them, they will map out your problems. Any p03XX is a misfire code. Just hope that if the car had sat for a long time without being started, that varnish (gooey build up from ethanol additives in fuel) didn't form on all part of your fuel injection & delivery system. If you get "lean" codes your fuel filter/fuel pump could be bad as the system isn't receiving enough fuel in the mixture to maintain stable acceleration. Go to Autozone or the equivalent, most places do a free scan.

As far as the oil leak goes here are a few things you can do to permanently knock it out:

1) Replace any sort of crank case breather hose (spider hose) at the back of the intake manifold.
2) Clean/replace suction jet pump & PCV valve
3) Buy a vented oil cap to replace the standard one
4) Replace Valve cover gaskets, cam chain tension gaskets & half moon seals
5) Make sure oil filter isn't leaking & drain plug. Sometimes crappy oil change places don't put thread sealant because they are mongoloids.

BTW the oil leakingness is quite common on these cars & if your tight on $ you bought the wrong car!

 

I just scanned the car and surprisingly throws no codes, since I changed the oil I have barely lost any oil over the last few weeks, weird, I'll keep checking though, thank you for the advise on the oil leaks though, I will try those out if oil keeps disappearing