How can I create Many to Many relationship?

A many-to-many relationship exists when one or more items in one table can have a relationship with one or more items in another table. For example: Your Order table contains orders placed by multiple customers (who are listed in the Customers table), and a customer may place more than one order.
To create many-to-many relationships, you need to create a new table to connect the other two. This new table is called an intermediate table (or sometimes a linking or junction table).