For windows users:
To download into a file open your cmd and folow this:
cd <*the file-path where you want to save it*>
pip download <*package name*>
the package and the dependencies will be downloaded in the current working directory.
To install from the current working directory:
set your folder where you downloaded as the cwd then follow these:
pip install <*the package name which is downloded as .whl*> --no-index --find-links <*the file locaation where the files are downloaded*>
this will search for dependencies in that location.