Connecting a Wi-Fi repeater to a captive portal Wi-Fi

I have two RJ45 Ethernet sockets in the room and thought of the TP Link Nano Router to connect them.

Do you know if it will be possible for me to connect it, although there is a captive portal? And if so, how to configure it?

You need to ask the school tech support about connecting a router to the RJ45 connection.

It should be straightforward to connect.

Connect an Ethernet cable from the RJ45 socket in the room to the WAN port on your own router.

Configure the WAN port to connect. This is where school tech support comes in. They will give you the connection parameters.

Now configure the LAN side of your router to a normal inside address. Likely it is 192.168.1.1 or close to that

Now you have your private network for your devices.

This should work. Good luck.