cat > user-data << EOF #cloud-config users: - name: termuxuser sudo: ALL=(ALL) NOPASSWD:ALL shell: /bin/bash lock_passwd: false passwd: $(openssl passwd -6 'ubuntu123') ssh_pwauth: true packages: - vim - net-tools EOF This creates a user termuxuser with password ubuntu123 . You can change the password inside the single quotes.
This guide will walk you through installing QEMU in Termux, setting up an Ubuntu virtual machine, and even accessing a graphical desktop (LXDE) via VNC. termux qemu ubuntu
Now create a meta-data file (can be empty): cat > user-data << EOF #cloud-config users: -