adfs3 and sharepoint confused

Hello

I was told to get familiar with adfs , azure and sharepoint for a project.

I don't know where the SharePoint will live (in-house or in azure).

I will assume I need some kind of sync between our current AD and the new azure environment, ( that if I do azure AD? right)

what do I use dirsync or AADSS or AADC.? https://msdn.microsoft.com/en-us/library/azure/dn757582.aspx

just getting overwhelmed with the options and TechNet articles. Am I correct so far that I need more information on the project/setup before continuing?

thank you