Hi DEASUNBEAG,
Thank you for posting in our forum.
Based on your description, may l know if you want to delete all the past meetings in your Teams calendar? I have done the relevant tests on our side, the best way to delete past meetings is to select the meeting and right-click to cancel it, or, as an invitee, you can decline it. We can not delete past meetings in bulk, sorry to inconvenience you.
If the answer doesn’t suite your needs, please feel free to feedback me with more details, thanks.
Best regards,
Nerissa