Tracks go into Locations but Mods distribute into multiple folders, not just into vehicles.
It depends a bit on how they zipped a mod or track. you can view a zipfile without opening it and if it has folders like Gamedata, rfm, UIData etc you know you can unzip to root (first level of the rfactor directory)
Basically the folders in a zip should mirror the folders in rfactor, then it gets placed in the correct folders.
I always check the zip first because some mods are not zipped correctly and then the contents gets distributed into the wrong folders and it doesn't work.
When in doubt, just unzip to a temp folder and manually copy the content of each folder into their mirror folders in rfactor.
Tracks is much simpler, they all just go into Locations, simple drag/drop or unzip into Locations.
One acception, some tracks are part of a pack and go inside a series-folder in Locations. (for example the GP79 mod has its own track-folder which contain a dozen tracks or so)
If there is a readme in a zip, read it