It is easy to upload the BOM. It will be cheaper to buy the Uno elsewhere, and maybe the sensors. But this technique makes an easy one-stop shopping for all the parts. Follow these steps:
Create an account on Digikey.com.
Go to BOM manager and select upload an order.
Upload the BOM file. It’s an XLS spreadsheet file.
Select that info starts on row 2 during file interpretation.
Use the drop downs to match names of the first several columns. The Digikey part number is the first. Quantity 3 is the last one that needs to be matched.
Process the file. Make a cart.
Review the cart. Delete the items you are sourcing elsewhere (e.g. the Uno, the sensors).
You might find solder paste cheaper in your local electronics supply store, but for convenience, you can add this to your Digi-Key order: Solder paste at Digi-key