First, we have the setup for Email and chat auto-deletion policies. By default, Do not delete email and chat messages automatically is selected, but you can change it so that messages are automatically deleted after a certain period—which, by default, is 30 days.

Once the selected period has passed, you can either choose to Move messages to the Trash folder or Delete messages permanently:

Keep in mind that messages in the trash folder will be permanently deleted after a few days, so it's a good idea to move them there first instead of immediately deleting them to minimize the potential of unwanted deletions and data loss.