Keypad control by Arduino - SriTu Hobby

Keypad Interfacing with Arduino Uno

Use a Keypad with Your Arduino - Projects

easy debounce button?

Debouncing a Button with Arduino - Programming Electronics Academy

How to Debounce switches on the Arduino?

How to Wire and Program a Button | Arduino Documentation

Arduino - Keypad | Arduino Tutorial

Keypad With Arduino Without Using Keypad Library (First Tutorial)