The problem with the send to Kindle option is email attachment size limit. For books it's fine but manga and comics are usually too big.

My Kindle is old enough that I was able to jailbreak it and install KOReader so I can just download from my Calibre server directly via OPDS. Otherwise if it's too big for email you'll have to do it over USB I think.

Not M1 but I tried installing Mint in my touch bar 2021 MBP and zero components worked. No track pad, no keyboard, wifi, Bluetooth etc.

Apple doesn't provide the drivers.