Rest API and device management

Hello everyone - I have below device.
I am looking for REST -API endpoint to manage the device locally. is there any package available where I can make simple rest queries ?

I wanted to check continuously who is connected to router.. and disconnect some one after some time.

Here is one link, but this does not work on my router. any pointers ?

Hostname OpenWrt
Model CUDY X6
Architecture MediaTek MT7621 ver:1 eco:3
Target Platform ramips/mt7621
Firmware Version OpenWrt 21.02-SNAPSHOT r16502-abf8209d7f / LuCI openwrt-21.02 branch git-22.167.28411-ee8170b
Kernel Version 5.4.108