Data: Connect to Cloud… menu and Open from Cloud button on Standard toolbar.
The first time you click it will ask you to authorize the google drive or onedrive connection.
Originlab only access and transfer user's data to user's computer via a temporary file on user's computer and no communication to anywhere else in that process
Click Account… to switch accounts in one service. E.g. user has multiple google drives. Can choose Google Drive on top, and then click Account… to switch to another google drive account.