Buy X Get Y Discounts

Buy X Gey Y discounts:

A type of discount that involves offering incentives on product(s) Y when customers purchase certain product(s) X. This approach is frequently used to boost the Average Order Value (AOV) and strategically manage inventory. This discount is also used well for Collections.

E.g: Buy 2 T-shirts & Get 1 Free, Buy Body wash & Face wash and get 30% off on Shampoo etc.

We have also seen brands like Conscious Chemist increase their AOV by +50% when using Buy X Get Y discounts.

How to create this ?