why do I have low oil pressure on 1997 Cadillac DeVille

My low oil pressure light came on warning to stop and is full of oil

Asked by for the 1997 Cadillac DeVille
3 possible things your oil gallies are plugged and won't let oil drain to oil pump or your oil pump is going out or your oil screen is plugged. do you have pressur cold?
do not have pressure when engine is cold
1 more answer
You may have a bad oil pump or the mains bearing in the engine are worn out. ADVISE TAKING TO SHOP IMMEDIATELY FOR DIAG. TO PREVENT ADDITIONAL DAMAGE