@NJin 
Did some search for Windows 11. 

Using the Registry, we can turn this Random hardware address option off. 

Launch Registry(regedit)

1. Locate the network adapter configuration that was configured with the random mac address feature in
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002BE10318}
The network adapter maker’s name can suggest the proper subfolder of {4D36E972-E325-11CE-BFC1-08002BE10318}.

2. Right-click on the folder that matches your device. For example, if the “0001” folder matches your device, right-click on the folder. Select New → String Value. Name the new value “NetworkAddress”.

3. Double-click the new Network Address entry. In the “Value data” field, enter your new MAC address. MAC addresses are 12-digit values, and should be entered without any dashes or colons. For example, if you want to make the MAC address “2A:1B:4C:3D:6E:5F”, you would enter “2A1B4C3D6E5F”

4. Restart the computer. You will notice in the wifi adapter advanced configuration settings that the random mac address option is greyed out.

In case kids also find this out. You can use Permission setting on that folder in Registry key. That would prevent standard users to make change/delete it.