Food gets freezer burn due to moisture loss and air getting to the food.
If everything in your freezer has freezer burn it's because the food is not stored properly and the air is not being sealed off to keep the moisture in the food.
Store food in airtight containers and wrap meats in tin foil along with plastic wrap to help seal in the moisture and keep out the air which will prevent freezer burn.
Freezer burn on food in the freezer is not bad as in the freezer burned food will not make you sick.
However freezer burn on food can be bad because it makes the food less tasty and less appetizing.
But you can still eat meat and foods that have freezer burn on them as there's nothing unsafe about eating freezer burned food as it does not make the food actually bad.
Bacteria is what makes food bad to eat but freezer burned food is safe to eat although it may not taste as good.
Freezer burn on food happens due to dehydration and oxidation, caused by air reaching the food and the color changes on freezer burned food are a result of the chemical changes in the food's pigment.
To stop freezer burn on food in the freezer you need to store the food in airtight containers or seal off the air to the food.