CouponFun is a extremely powerful plugin & this is perfectly fits for your coupons, promo code, discounts, offers, daily deals. It helps you to promote different types of offers.
After install go to “Pages” & add a new page (for example: Coupon), See right side “Template” drop-down option available select “Coupons” then Published the page.
Now go to “Coupons” custom post type here you can add unlimited coupon & discount offers.