I would start with some Pedal PCB builds ... their stuff is so popular you can get pre drilled enclosures for their builds off of Tayda .
And they have a TON of boards ... last I checked just Overdrives / distortions / Fuzzes were at 387 to choose from .... if there's a pedal you want ... odds are they have a cloned board for it . And then when something doesn't work ... you can learn the art of audio tracing ... and that IMO is where you learn the most ...
and as far as me building amps ...... I've already started ordering stuff ...... it won't be long ...