Do I need my key?

So I want to reset my laptop and I have now tried to read my office key so that I can use Word and so on. Now I'm wondering if I need the key at all, or if I can just log in with my Microsoft account and then just download my programs?

Why do you want to do that?

To correct an error or similar, it is sufficient to reset the computer to an earlier time, of which the software is not affected.

If you reset the calculator to factory settings you have to back up your data before everything. After that, you will be forced to sign in through a Microsoft account.