Captive portal installed on router - does it works on a connected access point as well?

new to networking here.

Need to create a hotspot for an event in a place without DSL/CABLE infrastructure, with a captive portal login - forcing session time and data usage limits.

I intend to buy a 4G LTE router (Tp-Link MR200/400) to serve as a broadband gateway, and install OpenWrt+NoDogSplash on it. for an access point, I intend to connect to it a Unifi AP AC Pro unit via LAN port.

my questions are:

  1. would captive portal policy active on the router be also implemented on the AP side automatically?
    i.e. a person that connects to the AP will get a splash windows in his browser window and his mac address will be registered with NDS?

  2. will the Captive portal, be active on the router's own WiFi as well?

  3. is it possible to create on the router side an IP white list, for an unrestricted access?

  4. is it possible to create an SSID with unrestricted access?

or, should I install OpenWrt & NDS on the AP itself, so it will run only on the AP side?

Thanks in advance,

let explain your questions

  1. yes but need better solution captive portal
  2. yes a lot of captive portal cloud based providers you can check I advice cloudwifizone
  3. yes possible ip/mac whitelist to access free internet
  4. No. Captive portal is help to manage wifi not SSID
    All captive portal run AP side and backside can manage cloud based. Good example cloudwifizone.