Looking at your relationships, you have 2 primary keys set in your Order Info table and Order Item Table.
The logical thing to do (it seems to me) is
1. In the order info table only have the OrderID as the primary key. The CustomerID is your foreign key and links to the Customers table making a 1 to many relationship i.e. 1 customer can have many orders.
2. In the order item table add and OrderItemID field to uniquely identify each record. Set that as the primary key and remove the primary key status from your OrderID and ItemID fields as these are your foreign keys to the OrderInfo and Item tables.
You then should have the following relationships
1 customer record - many order info records
1 order info record - many order item records
1 item record - many order item records