You can send a zip file in Gmail if you want to send a large file to someone without using Google Drive.

How to Use the Scp Command to Securely Send a File from Your Desktop to a Server Your email has been sent Learn how to use the scp command to transfer files securely with this step-by-step tutorial by ...

To download files from Dropbox, you'll need to open Dropbox in an internet browser and find the file you want.