Excellent, you created "add Instances layouts", so you may create instances and connect them.
Next in OrdaSoft Website builder
, please create "Show instance layout" for both Entities,
Please check: You need create 2 types "Show instance layout" with short details, where you show only some fields and "full details" where you show all info about one instance
Please check how create show instance layout
Next you need create all instance layout
, and there you need use "short show instance layout" as attachment.
Only after that please create "Child parent layout" it created very like as "all instance", only in "show all instance layout" you show only "Show instance" as attachment, but in "show child parent layout" - you show details of some instance and some child as attachment layout, and this "attachment" we loop. So you see details about parent and all child. and as parent you may use as "Book" and "Author"
and please check: in "show instance layout" you may as "redirect link" for field set link to other layout.
as example in short show instance layout, you may set link to details show instance layout.
and also set link to "parent-child layout"