Well, you're also following instructions that are more than two years old, confusion might be in order
Go yo your game library, and click on the Sims 4. After than you can click on extra contant, and your expansion packs will show below.
What content is not showing up? From which pack?
Open your Origin client and go to My Game Library, right-click The Sims 4 and choose Repair.
The 'I' isn't around anymore. Try to right-click the game in Origin and choose 'repair game'.
I do not work for EA
You might try deleting Origin's Cache, and if that doesn't seem to help try uninstalling/reinstalling Origin.
Clear Origin's Cache
If u have just bought it come off the game go on origin and in the bottom right corner you will have notifications. click on them and press the arrows next to the pack you bougt