Do you use a 2018 MacBook Pro? if so, WiFiSpoof is not compatible - as the ability has been crippled by Apple.
Otherwise, the change button only becomes active if you manually change the Address in the MAC address field.
The scrolling field is an advanced option, which allows you to spoof your address (using the randomize button) as the listed vendor. For example, perhaps you want your computer to still identify as an Apple device after spoofing - you would select one of the Apple Inc options.
Thank you for reply.
I have a MacBookPro Retina mid 2012 and I am not able to choose nothing than en0 and bridge0
I tried to deal with virtual interface in Network Settings, but I cannot change the bridge0 as Thunderbolt or ethernet Thunderbolt.
If I try to add a new virtual interface as ethernet Thunderbolt, all my settings of all my different networks vanish and I have to set them from zero.
May you help me to set the wired cable to use WifiSpoof functions?