what happen to coastline to atmosphere

I have tried many options. Including the one here in the description. Doesn't want to work at all, I'm tired of restarting the game. Maybe a video or a screenshot for this addon will help, how should I do it? I'm just suggesting.

if yall get stuck at the 2-1 just do the kill commad

#Svin first download the main mod on steam, and install on your drive C, then open your gmod location D:\SteamLibrary\steamapps\common\GarrysMod\garrysmod\cfg, open mount and enter that this line "Fast Detect" "C:\Program Files (x86)\Steam\steamapps\common\Fast Detect\FastDetect", save and lunch the gmod, you will have acess to the campaign of that mod and can use the maps like other regular gmod map

how mount this freaking mod