What are you classing as a game engine? There's quite a bit of difference between them all because most of the game makers (GameGuru, RPGmaker etc) are still game engines too but have less of a immediate learning curve than the game engines that do less of it for you. Most of the game makers you still need to code if you want more than a very basic game but you can make a game with drag and drop. It lets people start off by just looking at what code they need to do x thing they want to do though, so it is a good start for some. I, myself, have just downloaded Unreal yesterday after noticing it on the Epic Games launcher and thinking "I should try that", but haven't tried to use it yet, though I have learned some C#, html5, javascript, jquery, php etc through my study and I did mostly make a html5 2D shooter game type thing, but something wouldn't work for me and the lecturer was going to help me work it out in term break but then she didn't so I still need to go back and solve that sometime. I had trouble making randomly spawning enemies shoot bullets out of guns as it couldn't seem to work it out based on the coordinates of the enemy so the bullets would end up having stuff like x=NaN and attempts to fix it stuffed other things up unfortunately. I passed and I think I actually exceeded what needed to be done for the course, but it would have been a lot better if it actually was completely functional. Sorry I'm rambling on. It's just my one experience of making a proper game other than fiddling with GameGuru (which was only fiddling and no coding at that point so isn't the same as what I was doing making a web game - to do much exciting with GameGuru you need to use LUA but I was just fiddling with the basic drag and drop style functions). Most of the other coding I have done for study has been to make very basic "games" - like a game that counts how much you click on a square - and to make websites and animations for websites etc.
This sounds like it would be a bit of fun either way.