I can

I have run into this issue a couple of times on my Macbook Air. I have been able to download 2 mods but after about a week they disappeared so I was left cc and modless for a while which wasn't a problem. I have been creating sims lately and have found it very boring not having any cc and gameplay has also been bland without mods, I have been trying to download cc/mods constantly but every time I try my cc/mod .package/.zip never wants to enter the mods folder (look at the picture shown below) which means I am unable to play with them.

If you look at the first picture where I am trying to install a mod into the mod folder it doesn't work, but in a different folder, it will go into (the folder is highlighted in blue).

PLEASE HELP ME I RLLY WANT CC/MODS!!!!!