If you'd like to have a home page with some basic information on the book/contents of the website, you could have that here. I'm also putting a footer on each page with links to all the other pages. You can navigate between pages in the editor by going to the menu on the right, going to the 'Pages' tab, and clicking on a page. By double-clicking on one of the pages, you can rename it, and you can also drag them to reorder. Whichever page is on top becomes the 'home' page, regardless of page titles. You can also add a website tab by clicking the + button lower down on the Pages menu.
Also, feel free to mess around with the Themes menu on the right - I believe your options are somewhat limited, but find one that looks good to you. You can also make a custom theme if you'd like. I've selected a preset that I like, so you could always leave it if you don't have a preference, but there's no harm in experimenting with it.Â
You can also insert text boxes anywhere by going to the 'Insert' tab on the right, and clicking 'Text box' (somewhat self-explanatory, I suppose). With the theme that I have chosen, that will make the text box white on this non-white background - you can make it match by hovering over the text box, selecting the paint palette on the left of the screen, and selecting Style 2.