How Do I Make Maps Like Fivetowers & 6+1 Towers?

[Revaq]

I really would like to know how you make the marker that spawns randomly within a given area and when you enter it it gives you a set of random vehicles, then a new marker spawns somewhere else and does the same function.

The map is set out on open waters and players are spawned up on Towers, if they fall they die. I would like the markers to be spawned above the towerlan2 towers and some other objects too.

I have to admit that I am a newb when it comes to coding so I hope someone could help me with it.