There are images created specifically for termux. For example the link below is the first that I found.

https://github.com/EXALAB/AnLinux-App

This looks great, thanks!

EDIT: I ended up using UserLAnd, seemed a bit more highly rated, thanks again!

Something like that:

pkg install proot proot-distro ; proot-distro install ubuntu ; proot-distro launch ubuntu

I highly recommend using Andronix + AVNC