my ford f-150 has 100.000 miles on it, i have water condensation in my oil ,i need to change it, is it alright to flush the motor with kerosene without starting it and then change the oli and filter

Water in oil is possibly a sign of a blown head gasket.

Water will not condense inside the engine. If a small amount is present after sitting for weeks a tiny amount may show up in the oil, Any condensation inside the engine would burn off as soon as the engine is started and running for a minute or so. My best bet is a head gasket problem.

I think you’re right on the down stroke piston is pulling Oil from the oil return holes Of the head gaskets And going out the exhaust end of discussion