I need free software for my Daily sales / purchase in my General store that may use bar-code reader to see prices & updates sales and stock after sale purchase?

i should be able to store my stock info for example if i purchase 10kg suger that i upate in stock (Quantity +price) then i detecy its price using Bar-code reader and once sold 1 kg that is detucted from stock , and i shld be able to create / manage catagories . Will someone reffer me some software please .

I doubt there is free software available that integrates with your barcode scanner. What kind of reader do you have?