I want to start learning android dev and I understand that I'll need the android sdk and cli tools.
I want to try it in a kvm because even though it is open source, I would like to keep it separate from my main system.
Which distro and vm settings do you suggest I use? Any other tips or your experience with android development on linux would be helpful as well.
Debian is the best for your needs, because that's what Google uses internally too (they used to use ubuntu, but a few years ago they moved to a slightly modified version of Debian-Testing). All its engineers are using Debian-Testing at their desktops, so it's the best tested and tried distro for Android. Although all other distros are also expected to work fine.
I used garuda for a while when doing Android stuff and was really surprised that a lot of things like adb, fastboot and all the filetransfer stuff was working out of the box without even having to setup any android sdk, drivers, … . Not really a distrohopper however, so I can’t tell you if this is a common feature on other distros.