Can't merge 3 mods together in one other

Hi, i wanted to do this (in the title) but when i do exactly the same as the 2 videos on this topic ( like the one of northwesttrees) everything work until i launch the simulation, and they say that there is no mods in the mods folder ( in the run folder) but in my other working mods, there is nothing too but they totally works ! Please help me i'm stuck...(no not you stepsister xD)