80's Retro Cyberdeck

I'm having a bit of trouble visualizing your project. What/who is your LARP character ? 

So the Larp is basically Fallout but in the UK, The character is someone who has taken refuge in an 80's toy Store and has created a group based around, cartoons, music and pop culture cues from the 80's 

So instead of having like a 50's inspired Atomic Style pip boy, I am hoping to have it be a lot more electronic looking, with 80's style gridlines - Picture of the character below :- 

Have you got some pictures of the character's cyberdeck that you are trying to recreate ?

Processing is another language that you may want to consider for this
https://processing.org/

I haven't designed the Cyberdeck yet :D But I have the 3d printer for it, I am imagining something like the PipBoy in this but more 80's  #Pipboy 2000 Mk II -- Episode 417 

Is processing better for GUI?

Ah. ok, I thought you were trying to style it on an existing one rather than giving the old PipBoy an 80s makeover. 

Processing is quite good for getting up to speed with visual arts type stuff e.g.:

3D Terrain Generation with Perlin Noise in Processing
https://www.youtube.com/watch?v=IKB1hWWedMk
( There are around 1,200 videos on that channel ) 

There are two variants in use on that channel, the original Java based one with its Arduino style IDE and the p5.js Javascript library based one.

There is also the likes of Tkinter, Pygame, Pyglet, PyQt for Python.

ahhhh - kinda a mashup of Mad Max and Hell comes to Frogtown(Roddy Piper) with some body mounted electronic mono chrome screens.  You could do some cool stuff without needing the brains of an RPI5. Certainly an RPI5 would allow you to access stuff via wifi , or play some saved pre recorded videos from "HQ" and receive "distress calls"  , maybe even put a camera on your forehead for some facial recognition or object recognition , for example sound an alarm if identify a sword or ray pistol.  

Ooh that video is useful! I am still a bit confused as to what to learn (being a complete beginner) Do I carry on with Python or go with processing, as a lot of the project will be how it looks visually 

Yeah thats pretty much exactly it!!! I have bought an RPI5 already :D As I figured the wifi would be useful! But yeah those things above would be incredible!

Is Python the way to go? Or Processing as suggested above, as outside of the spec that I have a lot of it will be how the GUI looks

There is no easy answer to that question. Depending on the complexity of your project, you may even end up using several devices each programmed in a different language.

There is a good overview of the Python Tkinter GUI here:
https://www.youtube.com/watch?v=mop6g-c5HEY

Plenty of R-Pi related programming resources here to get you started:
https://magpi.raspberrypi.com/books
and I suspect some of the retro game books will have 80's themed graphics.

As Jan hints above, the RPi-5 might be a bit power hungry for this type of application.

Perhaps also take a look at some of the lower-powered alternatives like these ESP32 based devices with built-in screens:
https://www.youtube.com/watch?v=XaxYSqeFJ6w
Some of them are around $14 a throw.

There is no easy answer to that question. Depending on the complexity of your project, you may even end up using several devices each programmed in a different language.

There is a good overview of the Python Tkinter GUI here:
https://www.youtube.com/watch?v=mop6g-c5HEY

Plenty of R-Pi related programming resources here to get you started:
https://magpi.raspberrypi.com/books
and I suspect some of the retro game books will have 80's themed graphics.

As Jan hints above, the RPi-5 might be a bit power hungry for this type of application.

Perhaps also take a look at some of the lower-powered alternatives like these ESP32 based devices with built-in screens:
https://www.youtube.com/watch?v=XaxYSqeFJ6w
Some of them are around $14 a throw.