Unable to access Windows session even after reinstallation

Until now, I used my school account to access Windows, however this account has just been deleted by my school (end of study). I can no longer access my Windows session, the account no longer exists and I do not have another school/professional account. I told myself when reinstalling Windows I would be able to access a page where I could enter a Windows key, the problem is that I am only offered to connect via school/professional account. Do you know how to do it, either to correctly reinstall Windows and then enter my license key, or to skip the part where I am asked to connect to at least access a session and then be able to do something?
Thanks for your help, I really don't know what to do