vba for index match and return between workbooks

[TikuniZobri]

Hi folks. I only know the very basics to search and match on one sheet. What I need is to search match and return across two workbooks. I have the index of inventory and a customer order.
I need a macro to pull the item# when the file# match with the index. To make it more complicated, there are many index's by category (as seen in the image, this number is for electronics, but there's furniture, cookware, etc). So the macro has to first find the corresponding #Index using the value of the Order#, and then match the two file### to populate the item order.

Using excel 2003 at home, but need it to function with 2019 at work (fictional for both would be even better so I can tweak it from home). Many thanks for any assistance.

 

[GlennUK]

I suggest you merge all your reference files together into one workbook before you start.