The command error is as follows:
Pip is a tool for installing python packages that comes with Python. The error when using pip is mainly because the path of pip is not added to the environment.
The path of pip is added to the environment variables of the computer:
-Find the directory of pip.exe and copy the path of the directory
-Right-click "My Computer"-"Properties-" Advanced System Settings-"Environment Variables
-Find the "Path" in the system variables and click "Edit"
-Click "New" to paste the path you just copied in
-Open the command line and enter: pip list to view