There are no such coupons for learnDash but if you integrate with the AddOns of the LearnDash like WooCommerce then you can get the coupon option there.
Can I Give Coupon Code For LearnDash Course?
Update on March 17, 2020
There are no such coupons for learnDash but if you integrate with the AddOns of the LearnDash like WooCommerce then you can get the coupon option there.