"N O" wrote

Soon I'll be installing a new toilet in a bath remod I'm doing. I've
read somewhere that the distance from the wall to the center of the
toilet drain should be at least 14"... Is that correct. If so, I'm in
trouble because I only see 12"...

I think you are looking at older specs and the newer ones are 12 inches.
You have an installed drain there already right and are just replacing
around it? Don't fret. Just measure then go to the local hardware store
with the measurements.

My house was built in 1962 with the bigger older toilets. I probably have
that 14 inch. When we replaced the toilets with the newer 'low flow' they
sit smaller and there's a bit of extra space behind the tank. Harmless.