Inserting query based on a parameter from other table

Question

I have 2 tables namely:

 

tblRequest with fields id (PK,int), RequestedBooks (int), reason (nvarchar(500))

& tblResponse with fields id (int), BookDescription (nvarchar(50)), requestID(FK, int)

 

Now, if the requested books are only 3, how to make an insert statement for tblResponse that should only dispatch 3 books. Above that, It will deny the insert. 

 

Thanks again, everyone.