What all should I do to upgrade to Windows 11 from Windows 10 on a device after hardware change ?

Question

Hi.

I had been using genuine Windows 10 Home Basic for some time until I updated to Windows 11 Home Basic. My only drive was a hard disk, and Windows 11 worked flawlessly then. However, as the HDD started slowing down, I installed a new NVME M.2 SSD in the motherboard slot nearest to the processor. I thought I could reinstall Windows 11 to the new drive, selecting the option that I do not have a product key since the license is a digital license. However, I was unable to do this, so I performed a fresh install of Windows 10 on the SSD, hoping that I would then be able to update to Windows 11. But the update section indicated that the device doesn't meet the requirements, stating that Secure Boot is not enabled. According to the system details, Secure Boot is shown as not supported on my system, which previously ran Windows 11 without any issues.

After a long search on the web and going through many solutions, I did the following:

1. Changed the type of NVME drive where Windows 10 is installed to GPT.
2. Entered BIOS, disabled CSM, and enabled Secure Boot.
3. The NVME SSD is not shown as a boot device in the list; only the HDD is shown as a boot device, which still holds the Windows 11 installation.
4. Tried disconnecting the HDD SATA cable from the motherboard, but then no devices were shown as boot devices.
5. Reverted all the changes, and now the NVME SSD is shown in the list and currently holding Windows 10.
6. Deleted the Windows 10 installation on the HDD.
7. Now, the PC Health Check up app shows that my system is compatible for windows 11 update.
8. Tried downloading and installing Windows 11 directly from official website. However, some error msg was displayed (don't recollect the error code, sorry for this), restarted and auto reverted all changes made to PC and left with Windows 10 again.

According to CrystalDiskInfo, my current supported transfer mode is PCIe 3 x4, which might be due to my use of a 4th Gen NVMe SSD in a 3rd Gen motherboard PCIe slot. I presume this should not pose any problems, as the SSD's speed will only be limited to 3rd Gen specifications, which are still quite good.

Additionally, I attempted to download Windows 11 directly from the website and install it. However, during the final phase, an error message appeared, and the installation could not be completed. I previously read on the official Microsoft website that if any hardware changes are made, certain steps must be followed to proceed with the installation of Windows 11 on the same device again.

My motherboard is a Gigabyte B360MD3H(Intel socket).

So, it would be very helpful if I could get a briefing on what all changes are to be effected in the BIOS/SYSTEM etc before proceeding with Windows 11 update again.

Thank you.