Thank you for your question, Tami.  I am afraid that the photo is taken too far from the plant for me to see any detail, especially the "webbing" that you reference.    I cannot tell whether the "webbing" is from spider mites, spiders, or ?  The black spots on the leaves may be from a disease, insect infestation, or a water/nutrient issue.  This article lists known insects and diseases, some of which occur in the roots, and won't be apparent by viewing the leaves.  Getting an inexpensive soil water meter will let you see if the water is getting to the deep roots, and telling if you are applying too much or too little.

Are you able to some leaves and photograph them from no further than 6 inches, on top of a sheet of paper?  It would also be helpful to have you photograph some of the roots to see what shape they are in.

When and how you prune it depends upon whether you have a male plant, or a female plant.  If it's male, you won't get berries, regardless of its age.  I suggest that you read this OSU article about growing this species:  https://news.oregonstate.edu/news/growing-vigorous-kiwi-takes-care-and-strong-trellis

Perhaps you can help identify the problem(s) by reading what should be done to grow kiwi effectively.  Thanks!