@ridhgoswami
I suppose you are getting the import error in the IDE (VS Code). You can ignore this as long as you are not getting the error in the code. Sometimes the IDE is not able to detect the modules you have installed.
You don’t need to install anything in the VS Code terminal, and you should avoid using it altogether. Always use the external terminal.
PS: at this time, user-installed modules are not persisted at the end of a session. You’ll need to install this module every time you come back unless you install it in a virtual environment within your user workspace, which is persisted.