Thawing out shredded cheese is a bit of a different process from regular blocks of cheese.
The easiest way is to let it thaw out overnight by leaving it in the fridge. Four hours should do the trick. If you only wish to use a small amount of shredded cheese, put it on a plate lined with paper towels.
First, avoid microwaving your cheese to speed up the process. Microwaves work by heating the water in food items, which shredded cheese does not have much off. You'll end up with a messy, congealed gooey mess. Unless that is what you're going for, but the assumption is that you're not!
So what options do we have here? There are two.
Fill a bowl with lukewarm water, put the pack of shredded cheese in the bowl, and let it sit for 20 minutes. Use a spatula to move the bag around so the larger bits crumble, letting heat get to the bits stuck together.
If you do not want to use a bowl, run warm water on the top of the plastic bag for a minute or two and place it on the countertop.
Using a pan or oven tray, leave the plastic bag of shredded cheese on top of it and let the power of conduction do its thing. The metal pan will act as a heat sink and defrosting will be quicker than leaving it on the countertop.
Flip the bag over once in a while so both sides are in contact with the heat sink. Also, if you have a stainless steel countertop, you could leave it on top of that instead.
This process should take no longer than 45 minutes for a 200g bag of shredded cheese.