Me and a friend just got UE4 and would like to start working on games together. Is there a simple way for us to share the game files, or do we need to use dropbox or something? One last question, Could I by any chance add someone who is well acquainted with UE4 on skype, so that I can ask some specific questions, and get help if we need it?
You can use source control such as Perforce, I STRONGLY suggest against using Dropbox, as you’ll probably run into issues left & right. I normally would offer to help on Skype, but have had my fair share of that, and am quite busy as of late, perhaps you could ask around on the ‘Looking for Talent’ sub-forum.
As mentioned, use source control -> https://docs.unrealengine/latest/INT/Engine/UI/SourceControl/index.html
perforce - https://docs.unrealengine/latest/INT/Engine/Basics/SourceControl/Perforce/index.html
snv - https://wiki.unrealengine/Subversion_source_control_(Tutorial)
git - https://wiki.unrealengine/Git_source_control_(Tutorial)
Depending on how you will use the project you can also use dropbox/gdrive/… but source control is better 
You could join one of the skype groups -> there you can ask questions: