If this were a Debian machine, you could probably just crossgrade your existing amd64 install to arm64 and everything would continue to work. The process would involve qemu user mode until you move the SSD over to the new machine. Once the work of the Asahi Linux folks reaches Debian this will likely be possible for M1 machines, can they accept non-Apple SSDs?

https://wiki.debian.org/CrossGrading https://www.qemu.org/docs/master/user/ https://asahilinux.org/