So, I followed the videos for downloading mods, I have downloaded them and created a vehicles folder inside of my mods folder. But when I try to activate them through the 'mods' tab in the repository, I can't figure out how to get them into the game. Please Help!
That sounds odd. You just drag and drop downloaded .zip file to mods folder, you don't make vehicles folder at all and you don't take anything out from the .zip, just place zip into mods folder and that should be activated automatically. You get mods from here I hope and not from worldofmods? https://www.beamng.com/resources/
You maybe found a wrong tutorial. You don't have to create any 'vehicles' or 'levels' folder. Just put the ZIP in the mods folder. Nothing else. https://wiki.beamng.com/Installing_Content
That tutorial maybe be outdated, the new way it's simple Put the .zip folder into BeamNG.drive/Mods/Repo, and, you're ready!
I figured it out, turns out that when I downloaded them from the forum on BeamNG, it didn't download as a .zip file.
You probably found some very old mod or something (or your browser did something fancy) Most mods are in ZIP files when posted here.