I agree with all these answers. The next one must be from BILL.
We need more info. Anything. Brand names? Type of engine?
It has a head- gasket, atop a crankcase with oil, with a dipstick that smells of gasoline.
However, no mention of the problem. Oil in the gas makes smoke, a real golf-course no-no.
Gas in the oil, like a bleeding ulcer, will kill you. Also, a golf-course no-no.
A top-mounted carb may seep past the rings. A side-mounted carb will drip on the floor.
A mechanical pump can leak directly into the sump. Its not fuel-injected,,, computers don't allow leaks !
Like the doctor says, FIRST you tell me the symptoms, THEN, I'll tell you the treatment.