Read, measure pedelec signal?

Hi, iam new in arduino world but i need help with my project. :cold_sweat:
i would like to build android throttle control via bluetooth and connect it on the pedelec sensor on Arduino.
So when i will get pedelec signal i will get speed from andorid device and send it back to arduino and it will control it.
I already solve a connection and control with BT but now i need help with reading pedelec signal how i can read it through arduino. AnologRead? DigitalRead?

Thank you for help and suggestions.