Hello. I would like to know if I can use car mod and map in multiplayer
@evok- no no no ! mods can get you banned. and you can loose your gta 5 account. never go online with mods installed in your game.! these mods are for Single player Story mode only.
if you use Mods folder than you are safe to go online. but these mods won't work in online mode. they never do. and if you by mistake run the game with these on, you shall get a ban. so be very careful when it comes to online mode.
there might be alternative mods supported servers which host, moded game serves. but i am not aware of that. this above information is about Official Rockstar and Steam multiplayer option.