Connect the two phones using the USB OTG cable. The host phone (with Termux) should be connected to the "USB-A" side of the adapter, and the target phone should be connected to the "USB-C/Micro" side.
Before starting, you need two things to establish the physical and software link: unlock bootloader using termux link
This allows you to connect two phones together. Connect the two phones using the USB OTG cable
Unlocking your Android device's bootloader is the first step toward true ownership. It opens the door to rooting, installing custom ROMs like LineageOS, and flashing custom recoveries like TWRP. While this process traditionally requires a PC, you can actually and a second Android device. installing custom ROMs like LineageOS
How to Unlock Your Bootloader Using Termux: A Comprehensive Guide