Hello, thank you for reaching out to Microsoft Q&A.
To remap the Copilot key, you can use the PowerToys tool that can be downloaded from the Official Microsoft Website here:
https://learn.microsoft.com/en-us/windows/powertoys/
Once installed, go to the Keyboard Manager Tool to use the Remap a Shortcut Feature.
Enable the "Enable Keyboard Manager" toggle.
Copilot uses the Windows + SHIFT + F23 shortcut. To remap it,
Expand Remap a Shortcut feature not the Remap a key. Then, > Add Shortcut Remapping > Click the Shortcut (Pencil icon) and press "Windows + Shift + F23".
Select F23 from the dropdown arrow.
Then, in the Send section, select either Ctrl (Left) or Ctrl (Right).
Click OK, and the Copilot key should now work with your new remapping.
(Open the image in a new tab for easy understanding.)
Let me know if you still need more help.