Hi @Anonymous
You can use the Outlook connector to trigger the flow when a new email arrives. Then you can use either the Insert Row action (Excel) or Add Row to Table action (Excel Online) to add a new row to your Excel table. Providing your table is defined correctly in the Excel document, you will have visibility of all Columns as properties of the Action. Simply populate the Name column with the From value (Dynamic Content).
Whilst the above should meet your need at the moment, its likely that the file will grow quickly (depending on the number of emails you are receiving) and you will also have multiples of email addresses (no check for existing value in spreadsheet).