Complete noob here:
-Started on a shitty e-bike I plan on selling because I didn't want to sweat too much when commuting
-fitness is something I care about, I'd like to implement bike rides in my routines although not to an extreme level
-I use my bike mainly for urban commuting so I won't be going around in cycling suits panting and sweating or shit like that, I actually hate those
-Not being too tired/sweathy when I get where I want to get is the main thing that made me buy and e-bike, despite the fact I know they are bad
-I'm into mechanics and if I can build the thing it is more appealing to me
-I live in a bumpy uphill city and sometimes go on grassy and stony roads, so I was thinking an mtb
-If it has a lot of useless gearshifts it is appealing to me

Please suggest me a good bike that I won't have to change
Picrel is the trash I own