First Log into your cPanel: (Read Here How To Log Into cPanel)
This help assumes you are logged into cPanel:
Click on the Softaculous Icon in cPanel as in pic below:
Then Click on the Spanner Icon in Softaculous screen: and then on the ADD Backup Location Button shown below.
Then Select Either GoogleDrive or DropBox from the Protocol List:
You will notice a button to activate the GoogleDrive or DropBox Backup