Welcome!
I cant help you with the transition and workflow differences between two engines but here are some links to get you started:
https://docs.unrealengine/latest/INT/
https://wiki.unrealengine/Videos
Dont forget to use the search bar(on top of the forum page) first whenever you get stuck; it searches through forums, Wiki and AnswerHub, and feel free to ask your questions in the forums and report possible bugs to AnswerHub.