I want to use touch sensor (3 pins: 5V, GND, I/O) to power on and off lcd display module that goes on Arduino UNO. I already have an option with relay module and interrupt where I detect RISING bridge on an interrupt pin that later changes the state on digital output that controls the relay that powers on the lcd. But since I want to use these touch sensor for multiple things in my project I want to avoid interrupt collision and wonder if there is another way to do this without using interrupts? The problem is that touch sensor only gives high output when the finger is on it but I need it to change and hold every time the finger comes to it ( to work as a normal ON/OFF switch). Any ideas on how to accomplish this?
Just don't use interrupts, you don't need them for this. Just poll the pin, and keep track of states.
As a rule of thumb: you don't need interrupts.