If you have downloaded a legitimate content pack or mod in this format, follow these steps to install it manually:
: Use a tool like WinRAR or 7-Zip to extract the folder. Locate Your GMod Directory : Open Steam , right-click Garry's Mod , and select Properties . Go to Local Files and click Browse . Place the Files : Garry-Mod.rar
: Launch GMod to see the new content in your spawn menu or maps list. Safety Warning If you have downloaded a legitimate content pack
These files are often found on community sites like GmodContent.com or forums and usually include: right-click Garry's Mod
: Older mods or models that aren't available on the modern Steam Workshop.