I have a lincoln Mig welder requiring 230V 20A single phase power. I
have a welding job to do where there is no power available. It has the
Nema 6-50P 3 prong style plug.

I have a coleman 5000W run / 6250W max generator that has a 120/240 20A
4 prong twist lock style receptacle Nema style L14-20R.

Is this 4 prong receptacle 3 phase power? I purchased a 6-50 3 prong
receptacle, and L14-20 plug hoping to make some sort of adapter cable
so I could use my welder with the generator.

Is this possible with what I have? Can I just pull single phase 220
power from the X and Y out of the 4 prong plug (leaving the W
disconnected)? If not, is there a generator that has a 220V single
phase receptacle on it?

Thanks.