How can I add a coupon to the current user through the code?

Question

WordPress

How can I assign a coupon to a user, I have the following logic, if the user has 10,000 then a coupon for the next basket by 5%, 20k - 10%, 30-15%, how can I add a coupon to the current user through the code, only under the condition that he did not have it yet, thanks in advance, I will be grateful for any help