Can I install the gem file in the computer?

Yes, it's possible.

geminstall is the first to find the file in the current directory. If you look at gem reference

gem install will install the named gem. It will attempt a local installation (i.e. a .gem file in the current directory), and if that fails, it will attempt to download and install the most recent version of the gem you want.

geminstall tries local install first, and if it fails, tries to download the latest version.

And .Even if gem is in a different directory

gem install --local path/filename.gem

You can install it with the .