You can select the free product on the ‘Free products’-tab. When you tick ‘Allow multiplication’ and set ‘Minimum quantity of matching products’ to 1, 1 free product will be added for every matching product in the cart.
also is there a best way to turn off coupons? For example, I don’t want to delete a coupon but i want to deactivate it for now until I am ready to offer the deal etc
1. Set the publish date of the coupon in the future
2. Disable ‘Auto coupon’ and prefix the coupon code e.g. DISABLED-coupon-name
3. Restrict the coupon to Admin user only