Hi,
Are you upgrading from Windows 11 Home to Windows 11 Pro?
If so, this type of upgrade normally does not reset your PC or delete your personal files, installed programs, or settings. When you upgrade by entering a valid Windows 11 Pro product key, Windows simply unlocks the Pro features that are already included in the operating system.
The same applies if you purchase the Windows 11 Pro upgrade through the Microsoft Store. After the purchase is completed and the upgrade is initiated, Windows will upgrade the edition from Home to Pro while keeping your files, applications, and settings intact.
During the process, your PC may need to restart one or more times, but this should not remove your data. In most cases, the upgrade is completed without requiring a clean installation of Windows.
As a precaution, it is always a good idea to back up important files before making any major system changes.
Could you confirm whether you are upgrading from Windows 11 Home to Windows 11 Pro using a product key or through the Microsoft Store? Also, are you seeing any errors when attempting the upgrade?