How to communicate serial in a termux environment

Hello
We are trying to implement functions such as Nextion Touchpad by building a local server based on Termux and mqtt borker of an android phone. I installed the node-red-node-serialport pallet to communicate serial with Android phones, so I tried to connect my cell phone and FT232R USB UART with C to mini 5pin to receive signals. However, it is not possible to search for "Serial Port" in node-red-node-serialport during this process. So the link below allows usb to search on https://wiki.termux.com/wiki/Termux-usb
Termux, but it's still not searching. Is there any way? I'm sorry for my poor English. TT

A little unclear what you are actually trying to do here.

Are you trying to use the Android phone as a touchpad for something? Or are you trying to use a Nextion Touchpad with your Android Phone?

Also being worked on Stack Overflow here: