The python package installer pip is used to install packages in python. the syntax for usage of pip command is almost the same for the three major operating systems - Linux, Mac and Windows.
At first activate a python virtual environment and update the pip installer
pip install --upgrade pip setuptools wheel
Install the package:
pip install your-package-name
For example,
pip install requests
For specific version:
pip install "django==3.2"
To create a simple package for your local use, just create a directory with a meaningful name and create an empty file with name __init__.py inside the directory.
Create a module file , for example, my module.py and create functions and classes in the file. After completion, you can import this package in your local project.