Sims 4 Gallery OFFLINE?!

@CATTIPIGENX 
You need to be 16+ when registering an account with Origin.
If, when creating this account, you entered the age below 16 you will not have access to the Gallery.
If your entered age is OK please clean Origin cache

 https://help.ea.com/en-us/help/faq/clear-cache-to-fix-problems-with-your-games/

or
Uninstall the Origin Manually. See instructions here.
https://help.ea.com/en/help/origin/origin/manually-uninstalling-origin/
and install Origin again
http://origin.com/download

It is also possible that your connection configuration with Gallery is damaged in your game folder. In that case, you should do a factory reset of the game folder

.
Go to Documents/ElectronicArts - inside will be The Sims4 folder
Step 1. Rename The Sims4 folder to "The Sims4 old"
Step 2. Fix the game in Origin

Origin/Library - right click on TS4 - option "Repair game"
You have to wait until Origin will fix all packs, not only the base game.
Step 3. Turn on the game - a new game folder will be created and you will have two - one old, one new
Step 4. Check if you still have this problem in the newly created game folder
If the problem disappeared
Step 5. Delete in the new game folder following folders:
"saves" and Tray.
Step 6. Go to "The Sims 4 old" folder and copy - your "saves " folder.
Step. 7, Paste this folder in a newly created game folder.
Step 8. Do the same with Tray folder
Step. 9 If all is OK - delete The Sims4 old folder. Now you will have only one game folder which is working properly.

I don't work for EA