Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Since you are using Microsoft 365, your emails should be on Microsoft service, so you don't need anything specific to do on your new PC other then just sign in with your Microsoft 365 credentials.
However, I don't know if you have other accounts, or local only (PST) old emails on your old PC.
Go to outlook.com and check if all emails, folders etc. are there. If all are there, just login on your new PC and that's it.