Hi Jake. I'm Greg, an installation specialist and 9 year Windows MVP here to help you.
You wouldn't import your Mail accounts into Outlook from Windows 10 Mail app which is only a sync service like a phone Mail app, you would import the accounts just like you did into Windows 10 Mail app from their online account.
See here how to set up Outlook Mail:
https://support.microsoft.com/en-us/help/275890...
I hope this helps. Feel free to ask back any questions and keep me posted. If you'll wait to rate whether my post helped you, I will keep working with you until it's resolved.
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