I'm creating a 2D game where there are different backgrounds. I need to know about a feature where the different backgrounds can repeat one after another randomly.

I created different backgrounds in the game so I want a situation where the backgrounds will loop between each other. I mean, I will just follow each other, since it is an endless game I will like to separate the backgrounds and make it in a way that that background 2 will follow background 4 and just switch between backgrounds.

So that's what I mean, I hope you all understand.

I am using Unity and work with C#, the 2D game is not a tile game and I want the backgrounds to swap with each other and not for the background to follow the order in which they are built: I want them to swap, like, 1 to 3, then 5 to 2 to 4 to 3 to 2 to 1 and so on.

A better practice would be to generate an entire track before each session, but you could always make small random generated checks to instantiate your backgrounds.