SQL & PL/SQL

I'm trying to display a tuple from 2 tables but I am having issues trying to join them. This is what I have, assuming order.ord_id references product.prod_id

DECLARE
    	orderrec	order%ROWTYPE;
BEGIN
	SELECT 	* 
	INTO 	orderrec	
    	FROM  	order, product
    	WHERE 	order.ord_id = product.prod_id;
	
END;

Can anyone explain why this is not working? Is there a different way of joining in PL/SQL?