Keypad Alarm

This is basically 2 questions. For a final project in school, one of my ideas is to construct a keypad alarm system (very simplified). I am planning on having a 12 digit keypad hooked up so when the sequence 1 2 3 4 is pressed, the word OPEN scrolls on seven segment displays, if it's wrong, it scrolls CLOSED (I know how to do this). My 2 main questions are:

1 - How exactly do I wire up a keypad? Here is the one I am planning to buy:

Switches: Keypad - 12 Button

2 - How do I wire the circuit so when the correct sequence 1 2 3 4 is pressed, the word OPEN scrolls? I know how to wire the 1 2 3 4, but I don't know how to sequence it. For example, if 2 1 3 4 is pressed, the seven segments scroll CLOSED.

Thank you in advance.

Use a processor and do it in software - it would be a ludicrous thing to do in hardware.

I guess I should have mentioned, this was an introductory course. I was expecting this to be somewhat of an easy idea, because I would have no idea what software to use, or how do even do it in software.

So you're expected to do it in hardware?.

Yes. I believe so.

The scrolling display pretty much needs a microcontroller.