Also, how should I treat this type of cheese when putting it on pizza, shred it and spread it around or slice it like fresh mozzarella.
If you are trying to emulate the Papa John's style, you would dice the cheese finely. That is what I have been doing with my PJ clones. However, I see no reason why shredding won't work. Most places that use diced mozzarella cheese do so because of yield (better and more uniform distribution with less cheese). Also, pizza places that use “free-throwing” of cheese, or quasi-free-throwing, like PJ’s, prefer diced cheese because it is easier to scoop with their portioning cups and distribute evenly over pizzas.