Hi.
I recently make some snazzy eyebrows with TSR workshop, and I exported as a .package file - then right clicked, 7-ZIP, extract files... , EA>Sims3>Mods>Packages etc etc etc... and it said:
(See screenshot)
This is also my first time making my own cc for the sims 3 so there is a chance i may have done something wrong... ?

Sorry but, to be able to extract something with 7zip it's need to be a a file in a known compressed container as WinZIP (*.zip), WinRAR (*.rar), 7zip (*.7zip) and various others. *.package on the other hand isn't among them as it only relate to games.

So I am rather confused what you are trying to do:
A.1: Are you trying to compress the file in a container?
A.2: Are you trying to see the content of that *.package file?

Answers:
A.1: Then you should use, Click on File> 7ZIP> Add in Archive (or something like that)> menu pops up
A.2: You will need a *.package reader, try S3PE over at http://www.simlogical.com/ (If you are on a Mac, you might need other tools to run that progam on your machine otherwise it won't)

I am trying to put that package file into the sims>mods>packages folder so i can use it ingame. Thats what i usually do with the things i download - or can i just drag it in to the folder manually? (I'm really sorry i dont know alot about this stuff but i think i've sorted it out)

Thanks by the way :-)

(*facepalm*) Haven't thought about that third option , but yes, if it's already a *.package file and you want to test it out in your game, you can simply drag & drop or cut & paste it in your Mods\Packages folder. No need for 7zip to do that.