How can I make it that only VIP, and other ulx ranks can only open the garry’s mod context/props menu?
First off, you’d be better posting over here.
Secondly, to block the context menu from being opened, you could use the GM:ContextMenuOpen hook and check the users group there.
Next time, post here: https://facepunch.com/forumdisplay.php?f=65
Throw this in garrysmod\lua\autorun\cl_contextmenu.lua