What is wrong with this mysql INSERT statement?
There are two way to insert data:

if you have to insert data in Artical table with specific book title then do following

INSERT 
INTO Artical (title, price, book_id) 
VALUES (
    'Six faces of shadow', 
    15, 
    (
        SELECT book_id FROM book 
        WHERE book.title = &quot;Six faces of shadow&quot;
    )
);


if you want to add all book title with id then do following

INSERT 
INTO Artical (title, price, book_id) 
SELECT title, price, book_id FROM book

Hope this Help!!!