Windows 11 will not show incompatible drivers

How do I create the Enabled value?

First, let me say something that should have been said at the very beginning of this discussion, way back on Page 1 of what are now 9 pages.

Changes to the registry have the potential of damaging your computer. Please only make changes to the Registry if you feel comfortable doing so. Damage to the Registry may not be reparable by anything other than a full reinstallation of Windows. Some damage to the Registry cannot even be fixed with a repair or upgrade reinstallation. Some damage requires a full removal of Windows.

First make a backup of the entire registry with File / Export, and select the Export range of "All", and save the file somewhere you can easily get to it, like your desktop. This will let you restore it if you damage it. But trying to get back into a damaged computer to be able to restore it is well outside the scope of this discussion.

Also, I will note that the details must be EXACT. If you misspell something, or if you pick a wrong option like TonyTR did above, you may find a problem like I warned about above. But it's more likely that the misspelled entry just won't do what you want.

Now, to answer your question...

With "HypervisorEnforcedCodeIntegrity" selected on the left side, right-click in the open area to the right to get a context menu. It will only give one option - "New".
Select New. This will give you a new list. Select DWORD.

This will give you a new entry. Name it "Enabled".

Double-click on the new entry to open an Edit window. Enter a Value of 1, and click OK.

These changes to the Registry take effect immediately - you don't have to "save" anything. But you will have to reboot your computer for this particular change to do anything.

How do I create the Enabled value?

You may just need to click an arrow in front of DeviceGuard to show subfolders / subkeys:

See if it's really there. The subkeys are listed on the left side, not the right side - only the values are on the right side.

If you really don't have a Scenarios folder, you'll need to create it. Right-click on DeviceGuard, select New and Key,

Then type the new Key name:

Then create the HypervisorEnforcedCodeIntegrity key inside that:

Then create the Enabled value inside that:

See if that helps.

In your screenshot, we can't see the full key name, so I'm taking your word for having it spelled correctly.
The Type needs to be REG_DWORD rather than REG_QWORD.

And yes, there can be other reasons why it doesn't work for you. It'd be nice if MS still made stuff that operated in a simple and straight-forward manner with clear and specific error messages.

You mean like so? Yeah, still no dice. (So maybe it's not working for everyone?)