Sims 4 Won't Launch on Steam (+ Seasons isn't showing in my DLC list)

@smw008  Please uninstall the EA App with Revo Uninstaller (the free version is fine).  Reinstall it and restart your computer.  Open both Steam and the EA App as an admin: right-click each desktop shortcut and select "Run as administrator."  Only try to launch Sims 4 when both apps have loaded fully.

For Seasons, where did you buy it?

1. I don't have the EA app, I only apps I have that are relevant here are Steam and Sims 4 I acess via Steam. 

2. For where I brought Seasons, my dad bought it as a gift for me, and I am currently waiting for a responce from him.

Should I just uninstall Steam, or try something else?

@smw008  You can't run Sims 4 without the EA App, at least in Windows.  Steam will call the App when you try to launch Sims 4.  So it's there somewhere even if you have no idea where.

I don't play on Windows. I play on a Lenovo Laptop

@smw008  Lenovo is a manufacturer of laptops (and many other products).  These laptops have an installed operating system, usually Windows.  If you are playing Sims 4 on a computer, that computer runs Windows or macOS; it doesn't run in other OSs.  Since you don't have a Mac, your computer runs Windows.

And again, if you're playing Sims 4, the EA App is installed somewhere on your computer.  Steam won't launch the game without it.