Link two fields in one table to one in another

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MS-Access

I have a basic purchase order database in access 2016

There is a table called ItemData which has a autonumber key column ItemDataID, then ItemType, ItemManufacturer, ItemDescription, ItemCost.

In the Order Table there are various fields for supplier, delivery etc.
Then I want to be able to put in 5 order lines.

If there was only one line there would be no problem.

However I want to have ItemData1, (with all the other requsite fields as per above), then ItemData2 etc to ItemData5.
Of course for the relational DB to work the key have to be the same so changing then names will not allow it to connect (I think!).

How can I link the data from Item table to the 5 inputs needed on the Order table.

What I have tried:

Google, YouTube, Bashing brains on desk...