1) Product - Edit - Product Data

Adjust Min/Max Order Quantity, click Save Changes

2) Ensure any product Variants also have their MOQs setup, too 

Otherwise they will follow the same amounts as the parent product. 

3) Optional: Use with the "Customisation - Add Associated Product"

This allows e.g: "max one extra of this item per order" 

4) Optional: Use instead of Pack size

Previously you may have set Pack size to the minimum quantity. This allows customers to buy singles but with an MOQ.