Go to Woocommerce > Discount Rules in your dashboard.
Click ADD NEW RULE button to add a new Rule Setting.
Once you have finished setting up the rules, click the SAVE & CLOSE button.
Example: Buy 1 get 1, Buy 2 get 2, Buy 3 get 3, and so on
RULES SETTING:

WEBSITE VIEW:
Free quantities will be added to cart automatically and marked as Free.
