Gone is virtualenv. Here is python -m venv. In this video I'll show you how to install python3.8 and python3.8-venv on your Ubuntu Linux and then how to edit your .bash_profile to source activate that virtual environment every time you open a terminal. This is a good strategy to get yourself permanently based on a newer version of Python without messing around with the system that got pre-installed with the host OS, which you should almost always just leave alone. I'm doing this under Windows subsystem for Linux 2 (WSL 2) but it works the exact same way under just Linux.