In this video I show you the easy steps to install Python 3 on Pop_OS!. This worked on my Elementery installation too and should work on any Ubuntu base.
1. Open your terminal
2. Type and run: sudo apt update
3. Install software-properties (might not be needed) sudo apt install software-properties-common
4. Add the repo: sudo add-apt-repository ppa:deadsnakes/ppa
5. Install paython: sudo apt install python3.7 (or the version you need/want)
6. Check for version 3: python3.7 --version
7. set python3 as default: alias python=python3.7
Check out https://www.python.org/ for more on Python