Mikrotik external access point

Hello guys I have a question.
If I have 3 external AP for my hotspot, how to check or identify which AP the user is connected to in Mikrotik?

Each user has its own MAC address and can be found under wireless registration table…

To fully understand the question, what is the value, practical reason why this information is necessary or how will it be used.
(Are these APs MTs as well??)

No, the external AP only. I know in Mikrotik you can check the connected devices from wlan1 interface by going to wireless/registration.