magento2 – magento 2 cart price rule


I need to create cart price rule Buy x get Y with 50% discount ,Conditions are Buy 1 bag get 1 t-shirt 50 % offer

Scenarios
1], Bag 2 or equals or greater than t-shirt 1 -rule apply
2] ,Bag 1 t-shirt 1 equals or greater than – rule apply
3] ,Bag 1 t-shirt 1 – rule apply

How create this in custom can anyone help me or give ideas to create this?