rooted device: how to run SSH server persistent even on reboot

I (linux user but not an expert) just moved from iOS to android, my device is rooted (Samsung s9) and I want a ssh server running all the time on my android device (I prefer openssh over dropbear) since I have to rsync files. I also prefer linux style commands e.g., systemctl restart service or similar. I noticed that one can use Termux but it is an emulator, it won't work upon reboot. MagiskSSH seems to be interesting. Also noticed this thread where pre-built Native OpenSSH and BASH are shared. Also, I am not sure if they run upon reboot). Buildroot has also been suggested to compile the package on my own (but my knowledge is limited on this topic). On the top of this, I have to install rsync and bash. So, how do I run ssh server persistent (works on reboot)