Hello Rafapadilla93,
Thank you for posting in Microsoft Community.
I appreciate you raising this concern to us, and I understand the need to Reset your Surface. To answer your question:
After resetting your Surface Pro 9, you can upgrade to Windows 11 Pro again using your product key. Please note that you will need a valid product key for Windows 11 Pro to upgrade your Surface Pro 9 to this version. If you do not have a product key, you will need to purchase one from Microsoft or an authorized retailer.
I hope this helps!
Best regards,
Rolando S.