How do I produce code that will return a number between 1-6, then display the number.

I would like to be able to do this myself but so far I've only been able to find videos for 3d unity projects. I am unfamiliar with Unity so I don't know if those would work. If any of you have good tutorial videos or websites you could recommend that would be awesome.

I am not against getting someone else's code but would like some explaining on the code so I can start to get the hang of this.