Currently right now I’m about to purchase UE4 since for it being a entirely updated and advance engine and even having full access for only $20 a month is a steal. So far I want to know how long would it take would take me to learn all of the basics to begin working on the project. (I’m not a complete newbie, I’ll just be new to entering C++ from a Lua Engine before which was for 2D RPG Games)
I’ve looked at some of the other basic questions and see that it has built in server prediction that would handle the bulk of the multiplayer coding already.
Your question is highly subjective, but here is what I have found from using UE4 for the past month.
The blueprint visual scripting system is very good and you can get up and running with this quickly. Depending on what kind of game you want to make, it may be possible to do it entirely in blueprints and you won’t need to touch a single line of C++ code. If you want to make an FPS game you will find it much easier than some other types of games, but Epic is working on making other types of games easier to make in UE4 (such as the new Vehicle template that is coming in version 4.2 next week).
If you have a strong game programming background, you can probably get up to speed on UE4 in about a week using the blueprint visual scripting engine. C++ is going to take a lot longer to learn, especially if you are new to C++. Also, keep in mind this is a professional game development toolset. There is a lot to learn and I would recommend trying to find some other people to team up with, since making anything more than a simple demo is going to take a lot of work and you will need experts in various areas such as, 3D modeling, animation, AI, etc.
My suggestion would be to take a look at the official Unreal Engine tutorial videos on YouTube. This will give you an idea of what you need to know to make a multiplayer prototype of a game.
You should definitely buy it and try it out. It is an amazing toolset for creating games and it is a lot of fun!
If you didn’t already, you might get an impression of your own from watching the set of multiplayer videos from Unreal Engine on youtube. They make a very nice presentation, though of course the videos discuss ‘theory’ cases which have already been set up. The cases are minimal (ie, just 2 characters and a prop in a scene), but the concepts are useful.