Truck wont start, I kno the starters out but I shld be able to push statr amd it wont

I have a 1994 ford ranger, I started my truck one day and drove it maybe a block away, herd a tickin sound like my oil was a lil low but it wasnt got out of my truck to see waht it was pushed the acclerator nd it turnedoff coolent went from hot to cold nd it wont start, I pushed started it the other day it started for 30 sec. White smoke came out t
he exust and wont start, what cld be the problum I hardly have cash too keep tril and error this so I need help.