FiveM
Copy lks_gym folder to your resource one located on the server.
Add start to server.cfg.
RageMP
Copy the lks_gym folder into “server-files/client_packages/dlcpacks”
Singleplayer
Copy the lks_gym folder into “mods/update/x64/dlcpacks”.
Add “dlcpacks:/lks_gym/” at the end of your dlclist.xml in (mods/update/update.rpf/common/data)
Credits:
Lokas