Your storage is shared across Google Drive, Gmail, and Google Photos. When your account reaches its storage limit, you can’t send or receive emails.
To see how much space you have left, on a computer, go to google.com/settings/storage.
Clear space in Google Drive, Gmail, and Google Photos to make room for new items.
To delete your Google Drive files, move them to the trash. Files in trash will be automatically deleted after 30 days. You can restore files from your trash before the 30-day time window. You can also permanently delete them to empty your trash. If you delete, restore, or permanently delete multiple files or folders at once, it might take time for you to notice the changes.
You shall refer to the following link for the detail about managing Google Drive Storage. You shall learn 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 Trash and remove hidden data from apps in Google Drive.