Get well soon!
Well, there is a certain learning curve, but I promise the result is worth the “hassle”
Mainsail or fluidd does not make any difference in the end.
Option 1
The “Configuration” tab in the webinterface should take you to the correct printer.cfg to edit.
Option 2
To have a clean start, you may carefully and methodically work through Installing Klipper with KIAUH