I offered a starting point for the SQL query on another thread.
You will need to join prices to menu items which will also involve portions and potentially price tags.
As you will know portion is seperate to barcode as a product level detail so likely this will always be ‘Normal’ so next point is price lists if you have more than one.
SELECT p.[Price]
FROM [MenuItemPrices] p
LEFT JOIN [MenuItemPortions] s ON s.[Id] = p.[MenuItemPortionId]
LEFT JOIN [MenuItems] m ON m.[Id] = s.[MenuItemId]
WHERE m.[Barcode]=1234 AND s.[Name]="Normal"
That was how far I got but have multiple price lists which I think is what was causing the issue I was having.
As a non retail person without a scanner in any of my systems I didnt push further but is a starting point.