Pinpad security w/LCD using Arduino Uno

I'm trying to design a project that will use a pin code to activate a relay with a certain code. Also, I want to use a LCD screen to display "Enter Code, Code incorrect," etc. Here is exactly what I'm looking for but can't find any diagrams or write ups. https://www.youtube.com/watch?v=D9kWfl0zTJ0

Thanks for any help!

Show us what you have done so far.
Have you worked through the basic sketches which one with the IDE?

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