Car won't start on 1999 Chevrolet Cavalier

Engine cranks but will not start, I have spark to the pulgs, the Throttle body is getting gas, what can I check next? Is there a way to check the timing belt or a web site that shows the procedure?

Asked by for the 1999 Chevrolet Cavalier
does it have a crankshaft sensor in the block and is it ok.
not sure if it has a crank sensor but I have made some progress, and it's not good. Checked the compression in the cylinders, # 1, 2, 3 only have 25 to 30lbs # 4 has between 50 to 60 lbs. I don't know if it's worth putting any money into the car. The valves are moving because I took the top cover off, but there has to be something going on internally.
I would say she is done
1 more answer
check compression no compression no start