Upgrading Outlook 2010 to Outlook 365

diagdad Hello, never done it so can't say exactly how it's going to work. You can certainly upgrade, but you should at least backup some files. Settings are probably lost but are easy to configure, so I would focus on the data. I am attaching a couple of links to guide you in the right direction.

How do I upgrade Office?

https://support.office.com/en-us/article/how-do-i-upgrade-office-ee68f6cf-422f-464a-82ec-385f65391350?ui=en-US&rs=en-US&ad=US

Find and transfer Outlook data files from one computer to another

https://support.office.com/en-us/article/find-and-transfer-outlook-data-files-from-one-computer-to-another-0996ece3-57c6-49bc-977b-0d1892e2aacc

Export or backup email, contacts, and calendar to an Outlook .pst file

https://support.office.com/en-us/article/export-or-backup-email-contacts-and-calendar-to-an-outlook-pst-file-14252b52-3075-4e9b-be4e-ff9ef1068f91