Why is my cat shedding, biting fur, matting, and meowing strangely?

Ideally, take Buddy in to see your vet, so they can do a general physical exam and determine if there is suspicion for a problem with his skin itself such as an allergy, or if he seems to have any health issues that may be causing him discomfort (since he is meowing strangely). Cymric cats by nature have thick hair and a thick undercoat, so shedding is going to be more dramatic than in other cat breeds. It is sometimes difficult or impossible for these cats to groom themselves (lick their fur) well enough to prevent matting. Additionally, if he is painful anywhere (arthritis, etc) it is more difficult to groom. If his hair is matted, that can very uncomfortable because the matts pull on the skin. I suspect that is probably why he is biting at his hair. This discomfort could also be the cause of the pained "meowing."
It may be helpful to get Buddy in to a groomer. He may need to be shaved to get the matts off, and often this may require sedation. Therefore a groomer that works at a veterinarian's office would be ideal.
You can try to gently brush out the matts at home if he will let you, but if it causes him a great deal of discomfort or stress, don't overdo it at home.

Again, my first recommendation is to take him to the vet--if no reason for this behavior is found, I would recommend getting him groomed.
In the future to try to prevent the hair from becoming matted, brush him regularly at home (at least once a week), and you can try a product such as this:
https://www.petco.com/shop/en/petcostore/product/well-and-good-shed-reducing-cat-wipes

Thanks for asking PetCoach!