LightRP

This download looks like an addon. You need to extract the downloaded zip and put the addon folder in your Garry's Mod addons folder. You should end up with a directory structure similar to below:

• steamapps
  • common
    • garrysmod
      • garrysmod
        • addons
          • LIGHTRP <-- Addon folder!
            • e.g.
            • lua
            • maps
            • materials
            • models
            • etc

• LIGHTRP/
  • LightRP/
    • changelog.txt
    • entities/
      • weapons/
        • arrest_stick/
          • shared.lua
        • door_ram/
          • shared.lua
        • keys/
          • shared.lua
        • stunstick/
          • shared.lua
    • gamemode/
      • admincc.lua
      • admins.lua
      • bannedprops.lua
      • chat.lua
      • cl_helpvgui.lua
      • cl_init.lua
      • cl_scoreboard.lua
      • cl_vgui.lua
      • data.lua
      • entity.lua
      • help.lua
      • init.lua
      • main.lua
      • modules
      • player.lua
      • scoreboard/
        • admin_buttons.lua
        • player_frame.lua
        • player_infocard.lua
        • player_row.lua
        • scoreboard.lua
        • vote_button.lua
      • shared.lua
      • static_data.lua
      • util.lua
      • votes.lua
    • info.txt
  • README.TXT
  • Simple RP Prop Protection/
    • info.txt
    • lua/
      • SPropProtection/
        • cl_Init.lua
        • sh_CPPI.lua
        • sv_Init.lua
      • autorun/
        • sh_SPropProtection.lua

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