@CTBG_Pole_Digital
You need to figure out solution.
Install per-requirements. https://frappe.github.io/frappe/user/en/bench/guides/manual-setup.html
Clone bench of v3.x and install bench using ‘sudo pip install -e bench-repo’
then run following commands, hope it will helpful
bench init frappe-bench-v6 --frappe-branch v6.x.x
bench get-app --branch v6.x.x erpnext https://github.com/frappe/erpnext
bench frappe --install_app erpnext