FastLED Lights plus TV control Function with Keypad (and Z-wave)

Hello, I'm pretty new to Arduino and working on a project for a digital movie poster marquee display. The digital poster is a 40" LCD TV displaying a signal from a Windows 10 PC running a program called MoviePoster (as found on the AVS Forum.

Around the TV is a marquee frame with 48 WS2812B LEDs being run by an Arduino nano. I've been able to upload FastLED with a number of lighting sequences that I can control with a simple switch.

What I am hoping to do is control a few functions on the TV (power, volume, input) via an IR LED with the Arduino using a 3x3 matrix keypad. My hope you be to use the current Z-wave/Vera set-up in the home theater to "turn on" the Arduino and control the light sequences as ell as the TV. That seems like a lofty goal at this point but I've had another idea.

I have a Z-wave controlled power outlet that I can power the Arduino with. I'm looking to see if it's possible that from a powered off state both the Arduino and TV receive no power but once the outlet is switched on through Z-wave control that the Arduino boots, begins the first light sequence (which it currently does) but after a delay sends a "power on" IR signal to the TV to turn it on. The delay would be to ensure the TV getting power has time allowed before it can receive the IR signal.

From there being able to use the matrix keypad to control power, volume and input functions on the TV as the overall frame will obscure the IR receiver from using the TV's remote.

Being new I am a bit lost on how I might be able to combine multiple functions like this, connect and use the keypad and set-up the auto power function for the TV. I've been using Google and youTube looking for ideas and found many on programming the Arduino as a TV remote but none go into depth about using external keypads. I'm good at tinkering with things but need to find a good starting point to get myself going.

Apologies if this isn't in the correct spot as I am new to the forum. Any advice is greatly appreciated.

Attached is a Sketchup image of the final marquee display once it will be completed.