Install Odoo 8 link

Install Odoo 11 link

Install Odoo 13 link

Install virtualenv

pip3 install virtualenv

Create a new Python virtual environment for the Odoo installation

cd /opt/odoo

virtualenv -p python3 odoo11-venv

Activate the environment

source odoo11-venv/bin/activate

Install all required Python modules

pip3 install -r odoo11/requirements.txt

Deactivate virtual environment

deactivate