the ideal way to build games in unreal is use to both blue prints and c++ together!!!
the number 1 game in unreal engine right now is fortnite and that is built using 80% blueprint code + 20% c++ code together at the same time!!!
its up to you how much of each you use, but 80/20 is a pretty good ratio, 80% blueprint for the light demanding code, and 20% in c++ for the heavy stuff.
but when ur starting out u might want to go 100% blue prints, until you think u ready to release, and then add the c++ at the end.