Guidelines for Deleting Large Files in Google Drive
This webpage can also be accessed through Drive Settings > Manage Storage
Sort by ‘Storage used’ column to view your largest files
Delete files as needed. Files count toward the overall storage limit of the account until they are removed from Trash in 30 days.
To expedite this process, navigate to ‘Trash’ on the left, right-click an individual file / folder and select Delete forever or select Empty trash in the upper right to purge all files / folders. Confirm by clicking Delete forever.
If files have been copied to Shared Drives, scan through the contents of accessible Shared Drives and trash files as needed as this data may be consuming twice the storage space.