Couldn't find any package by glob 'Python-3.7.0'

In Ubuntu 16.04 open the terminal and type:

sudo add-apt-repository ppa:deadsnakes/ppa   
sudo apt-get update   
sudo apt install python3.7    

Alternatively you can also install Python3.8 in Ubuntu 16.04 with the following commands:

sudo add-apt-repository ppa:deadsnakes/ppa   
sudo apt-get update   
sudo apt install python3.8  

To show the Python 3.7 version run the following command:

python3.7 -V

To start the Python 3.7 interpreter run the following command:

python3.7  

To exit the Python 3.x interpreter run the following command:

exit