Sorry, I really can’t help you.
But a plumber once told me that you only need to know three things to be a plumber.
Excrement runs downhill.
The boss is an SOB.
And payday is Friday.
I’ve had to avail myself of the services of good plumbers a couple of times, and I’ve been very grateful for them.
They need to know a LOT more than what you suggest :-).