HELP PLEASE

so to preface this before i get into details. Hi, my name is Jessica and I use my fiancé's EA and steam accounts. Both of his accounts are linked together.

I had purchased some expansion/stuff packs, including seasons, life and death, rent, cats and dogs, get to work, businesses and hobbies, laundry. 

It says that they are not installed. How do I install them onto my games, I have looked at some other players issues/problems, and I tried using some of those solutions but none of them have helped. Unfortunately, at this point I am getting fed up with it and I'm not wanting to continue playing this. this is unfortunately my last resort if I can't figure it out, I will just kiss my worlds and money i have spent on go to waste. 

Please any help/information/guides will be greatly appreciated. I'm praying that someone can help or give me some guidance.