I downloaded TF2 yesterday. I am liking this game. I found out that there are mods and skins available online. I also found tutorials to use these. But I am not sure if I would get banned for using them. May someone please tell me?
Custom skins are client side and do not interact with VAC. This means you cannot be banned for using them. It is possible, however, for servers to disable them by changing certain settings.
"Mods" covers a wide range of things from perfectly legal scripts to completely illegal aim-bots and hacks. Without knowing the exact mod you're talking about, I can't say whether it'd be allowed, potentially disabled or illegal.