does the broiler work to broil a steak? the broiler may light and stay on 100% as opposed to the oven cycling burner on/off.
it may be the thermocouple but if the assembly is damaged it's not cost effective to replace the entire oven gas valve with thermocouple.
some years ago in the 1970's we had a visitor once to one of our apartments helpfully turn on an old gas oven which had no pilot light but required manual lighting. the oven filled with gas, the tenant herself smelled gas and belatedly lit the oven, the gas exploded and promptly singed all her facial hair and sunburned her face. the visitor said "oh, i thought it was supposed to light itself". they cancelled their plans for cooking a frozen pizza that night. there was no fire, everyone survived and recovered.
this is the time to also consider the 2.0 cubic foot microwave big enough to cook a turkey.
consider a safer alternative replacement gas stove with electronic ignition that will pay for itself in savings on the gas wasted on pilot lights.
if you are still inclined to waste time fixing a potentially lethal appliance, there is a brilliant genius at the other end of this site which is packed with free repair tips and pay manuals and pay parts:
on top for your top burners: soak the top burners and clean out the pinhole that points toward the pilot light. remove and clean the spiderwebs or food out of the tube that leads from the flame to the burner.