Well, I guess it kind of depends on what sort of game or gameplay mechanics you want to put together. Your models are done so that’s a big step, but what about your animations? Are your models going to do anything?
Anyway, let’s say for instance you are done with your models and animations…for somebody who is completely new to 3D work in general, with 10 hours a day you may get up to speed with the basics in as fast as 2 weeks. When I say basics, I’m talking about following the documentation that Epic provides. Particularly the “Getting Started With UE4”. This will cover the basics of the interface and working with models in the editor. However, anything beyond that and you may start to struggle through the documentation. There will be terminology and concepts you won’t understand.
If you are looking for a fast pass for putting a game together, you won’t get much done without the basic knowledge of all the components that make up a game. The game engine is a system of software where the culmination of your 3D models, textures and animations (just to name a few) come together. If you don’t know the basics of any of that, you won’t get that far. Just a warning. Not to discourage you of course. With 10 hours a day, and some willingness you can get a lot done. Just realize, it takes time and a persistence to learn game development.
Try starting here: https://docs.unrealengine.com/latest/INT/GettingStarted/index.html
And ask questions if you need help!
Also, for a “good” project to finish, for somebody who has no experience, your looking at least a year. Most likely two years, depending on how much work you put into it. If you work hard at it, and you have some artistic ability you can make a lot of progress in just 6 months.