I am going to build an interior wall in a room where there will be a closet behind. There is an outer wall behind, so it can be as simple as possible, it doesn't need any soundproofing. There will be paneling on the wall facing the room. What do you need to put on the wall besides the paneling? And how thick do the studs need to be? I've never built an interior wall, so answer as if I'm an idiot 
Hello
This is a good place to start reading.
https://www.byggbeskrivningar.se/renovering/bygga-innervagg/
This is a good place to start reading.
https://www.byggbeskrivningar.se/renovering/bygga-innervagg/