Can I force customers to buy a specific product or variation with every purchase?
The WooCommerce Quantity Manager plugin lets you set a minimum quantity of a specific product that can be purchased.
For example, let's say that you have a product called 'Chocolate Cookie', and you have set a minimum product quantity of 5. This means that customers can only buy the Chocolate Cookie product if they select a quantity of at least 5. However, there is nothing forcing them to buy the Chocolate Cookie product - they can still buy other products from you, without any Chocolate Cookies.
If you want to force people to buy a specific product with every purchase, then setting a minimum quantity is not the right solution for you. Instead, you need one of these plugins: