This will show you your Google Drive storage usage and show you which area is using the most space https://one.google.com/storage
Manage files in your Google Drive storage
Use this link to have Google help you manage files and clear space https://one.google.com/storage/management
And this link provides lots of help https://support.google.com/drive/answer/6374270?hl=en-GB such as how to …
- Delete files by size in Google Drive
- Permanently delete large emails in Gmail
- Permanently delete emails in your spam folder
- Move photos & videos to the Bin
- Delete and recover files using Google One storage manager
- Remove hidden data from apps in Google Drive