checking normalisation

the database is a college project for a warehouse business who sell many items. i am very new at normalisation, so i was wondering if someone can check and suggest any changes.

Customer [CustomerID, Customer Name, Business Name, Address1,
Address2, City, Postcode, Delivery Address1, Delivery
Address2, Delivery City, Delivery Postcode, Telephone]
Order Info [OrderID, CustomerID, Order Date, Delivered Date]
Order Items [OrderID, ItemID, Quantity, Selling Price]
Item [ItemID, Item Name, Description, Quantity, Actual Price, Stock
Level]

Normalisation has to be upto 3rd normal form
thanks in advance for any help

You might consider adding an 'Address Type' field to your customers table. Then you could drop the additional 'delivery address' fields. Address types could be 'Contact, Delivery, Both' or something like that. For everyone that uses the same address for both purposes, you save space, plus your data will be easier to search and maintain. You would probably want to add a table to hold legit values for Address Type and establish referential integrity with your addresses table. This would allow your customer to have as many addresses / address types as they wanted.

As a practical matter, a lot places have more than one phone number too. Another table for phone numbers and types, maybe? If needed...

Other tables look pretty normal! Good luck.