Sim 3 thing's to remember before adding mods, furniture, clothes etc

I haven't played the Sims 2 in 8 years or longer and have gone through many PC's etc over the years, so all notes on the Sims are lost and I forgot if any ini tweaks are needed to make clothes, mods work and appear in the game right?

Well clothes, hair, mods etc work where the game is installed in the Steam folder?

Any script extenders or tools or color extension files needed? I remember some enabler mod for community made color alterations or furniture tweaks for the sims 2 years ago , anything like that needed for the Sims 3?

Are there any recommended most have bug fixes for the game?

I know skyrim and it's bugs and mods, but I'm a born again virgin of knowing where to get started with the Sims3 ?

Owe it's the Sims 3 I'll be playing

thank you Craig