The Sims 4: Laundry Day Stuff Pack how can I uninstall it?

@RevkaKoala  Technically, you could just delete the Laundry Day folder: SP13, inside the game's program files.  If your computer runs Windows and you never changed the default install location in Origin, the full file path would be:

Program Files (x86)\Origin Games\The Sims 4\EP13

But Origin will try to redownload the pack again, even if you've disabled automatic game updates in Origin.  With auto updates disabled, I think Origin will try to download after any repair or patch, or after you clear its cache; and it may start the download when you launch the game, so be sure to tab out of Sims 4 and cancel the download.  Disabling auto updates may make it happen less often though: hover over your username in Origin, select Application Settings, then under the Application header, scroll down to Client update and disable auto game updates.

The alternative is to simply disable the pack from loading:

https://sims4.crinrict.com/eng/2017/03/disable-single-packs/