check engine light is on, when i try to pull code it just stays solid instead of blinking/flashigh like it should to read the code.

about every 1 in 4 times i start my car it sputters and stays below a thousand RMP and doesnt wanna run, it tries to stall and stall unless i give it gas and shift really fast into drive. Yes, it's automatic. I was going to do a 5 spd swap soon but with these problems who knows when that'll happen. It has always idle jumped, but now when i start it and it doesn't sputter, it just idles really high, like 2k+ RMPs and doesn't jump. There's a stain on the underside of the hood, over what would be the bottom right side of the engine looking at it from over top, if the hood is closed. It looks like oil. I've only had this car for 2 months so I'm not sure when the last time the oil was changed or anything. What could this be? Feul pump? I'm pretty new to mechanical issues and I'm only 17. Somebody help please haha

oh and if i let it sit in the on position before turning it over, I think that helps it start without wanting to die... I read somehwere that doing this allows fuel to run through the lines? I'm not sure. Any help is much appreciated