help with some issues

ok first off the car is a '00 Sentra XE...5spd, 1.8L Twin Cam (sisters car)
after about 52XX miles i finally changed out my sisters car oil since the last time...but just this morning before i changed it out when she started the car after about 5-10 seconds it would struggle to stay on and then just died...same thing happened 2 more times...so now AFTER i change the oil same result...it only stays on by giving it a little gas to keep the rev up...so i drove it to run some errands (only car available) and it started to smoke...now my dad was the one who took out the oil filter and when he did some oil spilled on the oil pan and around that area...some also got on around where the header connects to the exhaust...now when i popped the hood the smoke seemed to be (not exactly for sure) coming from just around where the header connects to the exhaust...so i figured it might be the oil burning...but now i just got home not too long ago from work and it was smoking when i got home...this time from where i didnt pay too much attention but it was smoking and the usual it died after not keeping up the rev for a few seconds...so any idea guys...any help would be greatly appreciated

hmmmmmmmmmmmmmmmmm sounds like theres no way to be sure that the smoking isnt just coming from the oil dripping on the exhaust and burning off. but theres no oil light? check spark and put a pressure guage in the fuel system return line.

nope no oil light...could it possibly be a sensor?

possibly but check easy stuff first. make sure theres good spark and fuel, then check compression and manifold vacuum.i would think about investing in a chilton manual, if you want to do work on cars, its helpful.

spark plugs seem to be somewhat toasted...ill change those out and than well see the results