How To Install Python 3 on Ubuntu 20.04
Step 1 : To see which version of Python 3 you have installed, open a command prompt and run
python3 --version
Step 2 : To use a more current Python, we recommend using the deadsnakes PPA to install Python 3.9
sudo apt-get install software-properties-common
sudo add-apt-repository ppa:deadsnakes/ppa
Step 3 : Enter the following command to run Update local repositories
sudo apt-get update
Step 4 : Install Python 3
sudo apt-get install python3.9
Step 5 : Open a terminal and verify that you can run Python 3.9 from the command line
python3.9