Removing Excess Emails [Edited]

I had my computer cleaned of some malware then Xfinity down loaded 34,700 emails into my computer and stopped sending emails on 3/31/2025.

Can Xfinity remove the excess emails from my computer and all emails except the 90 days from their archives?

That would be a big help right now.

Thank you for what ever help you can assist with.

Paul [Edited: "Personal Information"]