I tested out on Win 11.
From a command prompt:
------------------------------------
wsl --install
wsl -d ubuntu
rsync --version
rsync -zavh --delete /mnt/c/Users/username/Documents /mnt/c/.....path of folder for backup...
------------------------------------
Explanation
wsl --install - Installs the Windows Subsystem for Linux.
wsl -d ubuntu - Starts the WSL distro called Ubuntu.
rsync --version - See that rsync is installed and the version number.
rsync -zavh --delete /path1 /path2 - Run the command for the backup.
From a command prompt:
------------------------------------
wsl --install
wsl -d ubuntu
rsync --version
rsync -zavh --delete /mnt/c/Users/username/Documents /mnt/c/.....path of folder for backup...
------------------------------------
Explanation
wsl --install - Installs the Windows Subsystem for Linux.
wsl -d ubuntu - Starts the WSL distro called Ubuntu.
rsync --version - See that rsync is installed and the version number.
rsync -zavh --delete /path1 /path2 - Run the command for the backup.