How to track affiliate sales made on third party websites through our affiliate link?

There are two types of users 1- Brand 2- Influencer

Brand adds a campaign that influencers will promote with their social network. Brands also provides a coupon code that influencers use in their post that leads to the selling page of the product. (eCommerce platform can be any)

Now my main concern is, how can I track either sale is made using that coupon code or not. Need to store that information in database.

Thanks, Rizwan