Can one add expansions from this place if u already have the game?

I'm having some trouble playing the sims here, and i wondered if i could still add the expansion packs to the game if i bought the game and used this website to add the expansions?
Whenever i' am playing sims, after about 5 min, the game will suddently start to bug. The game animations will continue to move and so on, but the time stops and i'm not able to interfere, or click or pause the game for about 5-10 seconds and that goes on and off every 15 seconds. i've tried to start the game over again, tried new saves, but nothing works? i have 9 different expansions and the original sims, all from your website, did i do something wrong while downloading, and if not, what can i do to fix it?

Yes, you can, but it won't make any difference regarding the "freezing".
The same problems are still there when you buy the game.

You can install the complete "Origin" game for free via ZLOrigin. Advantage of version 1.69 is that you then can switch off certain packs to ease off the workload for your computer.