Hi Ganner, welcome to the henhouse.
I would recommend you buy a couple of good books to start with. The Haynes Chicken Manual is a very good book for beginners (and not so beginners!).
After an initial settling in period, chickens will automatically put themselves to be in the hen house at dusk, but it is recommended that you keep them penned in a smaller area until they are familiar where "home" actually is.
How high they fly is very dependent on breed. Some are very good flyers (leghorns and appenzellers), some don't fly at all (Brahmas). Most middle weight laying hybrids can probably clear a 4-6 foot fence, especialy if they have something to launch off, but mostly they will be happy to stay on the ground if they have food, water, somewhere to dustbathe and somewhere to perch. If your field is exposed then they will also need an area which is protected from the wind and rain.