how to install with pip for python3 code example

Example 1: installing pip

python -m pip install --upgrade pip

Example 2: install pip3

sudo apt install python3-pip

Example 3: install pip in python

python get-pip.py

Example 4: pip install python 3

You cannot just pip install python3 because it is not a library.

If you want to install the latest python3:
https://www.python.org/ftp/python/3.8.2/python-3.8.2.exe