It does not work like this here.
Here is what is expected of enquirers:
1. TRY first what you want to do! You may find that it's not that hard.
2. Formulate what was done by you that looks like an issue/not working.
Try them and tell if you face issues.
Members will be more than happy to help like this.
For now, to start with, steps:
1. Design a webpage that thats ItemName and quantity
2. Save the Item with quantity in database, where you maintain every entry via BillID
Following will help you to learn on how to talk to DB:
Simple ADO.NET Database Read, Insert, Update and Delete using C#.[
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