Hi,

We have an option Discounts and Loyalty in both enterprise and community of V16 , from there we can select the program type as Buy X get Y . There we have two options to set the conditional rules for free product and the reward as your free product.

Regards

in V15, you can make it simple, for e.g offer is : if we buy conference chair 3nos, one conference chair is free, in the promotions configuration set the minimum qty as "2", now if you create sale order for 3 and click the promotion button, odoo will automatically add the offer line item and make it as negative price, now the sale order will be raised for 2 qty only and customer needs to pay for 2 nos , sale order qty will be 3. EDIT: on the other hand, if you add qty 2 nos in sale order and click promotions button, no free product will be added to sale order, and hence the above procedure works fine!! check that, and if you find this answers your query mark it as Answer please

The behavior requested in the original post is now standard behavior in Odoo 16 :) 

Could you help me about this? im having same problem, What did you do or what method did you modified to apply this feature?