I want to have a copy of my Microsoft Excel and Word documents in offline mode. Is there way to to copy or backup those files with scheduling tools everyday or another  automatic sync software that do it for me?
Using google drive (Google Docs) in offline mode
google drive
You can use Google Cloud Connect to have Google Drive act like a backup of the files that you open in Microsoft Office. It automatically syncs with Google servers whenever you do a save, so you can be assured that your documents are safe online in the cloud.This plugin also allows you to open Google Drive documents in Microsoft Office, so that the environment where you edit documents stay the same. The only problem is that Google Documents format isn't supported.