Hi I wonder how I can install a package in Sims 4

@sjobergjulia  There is no official way, but unofficially, you can simply delete the packs' folders.  Make sure the EA App is closed and, for Windows, the EABackgroundService is NOT running in the Task Manager.  In Windows, the packs are directly inside the Sims 4 folder wherever you installed the game, here by default:

C:\Program Files\EA Games\The Sims 4

or

C:\Program Files (x86)\Steam\steamapps\common\The Sims 4

In macOS, there's a "The Sims 4 Packs" folder next to the Sims 4.app wherever the game is installed, typically either in Applications or Users > your username > Applications.

In either case, here's a list of available packs by folder name:

https://sims4.crinrict.com/eng/extras-2/available-packs-dlc/