Step.1 Go to App Admin -->InstaPlus Shoppable Instagram --> Tag & Moderate posts.

Step.2 You can see all the Instagram feeds here, now click on Tag Products to tag the products.

Step.3 When you click on tag products you will see the + sign from where you can add products and after adding it you need to Save it. 

Step.4 You can see on the frontend the tagged products are showing in below given image.