What generic conventions should I follow in writing a book review?
Normally, a Q&A should consist of no more than two closely related questions. In this case though, you really are asking a single question about how to format a book review. The main answer is that you should follow the format your teacher has specified, just as professionals follow the standards of the place in which they are publishing.
Title: Normally, just use the title of the book, “A Review of ABC”.
Divide the review into sections by using sub-headings in boldface. Do not start a new page for a new section. Just place two blank lines after a given section, then the subhead for the next section, e.g.
A Review of …
Text of introductory section
Text of author section
Text of summary section