Re: Do I have to buy expansion packs?
The Sims 4 is the base game, if you want you can add the expansion packs, stuff packs and game packs. But you don't have to.
If you want any of the expansions/packs you'll have to buy those separately.
Expansions always come on disk, stuff and game packs get merged in to one bundle and you can get those as well, or get those as a download through Origin.