Please be aware that most carriers, especially Royal Mail, are still experiencing delays in shipping due to Covid.
Yes, you can leave any title, caption or text boxes blank and your book will print normally. Look in Preview to see how it will print.
When you cut and paste from Word it sometimes leaves a space at the start of a new line. Try and delete normally, but if this doesn’t work, delete the space and press shift and enter at the same time to start the new line of copy.
You get a better result if you use the + and – buttons on the top left of the screen rather than your keyboard Ctrl + or –
Ctrl + A selects all; Ctrl + C copies; Ctrl + V pastes. On a Mac replace Ctrl with Cmd.
Click on the caption just once. A black box appears. You can now move the caption and change the size of the box.