The answer to 'why is my silverfish bites' is that silverfish do not actually bite humans. Silverfish are small, wingless insects that feed on carbohydrates, proteins, and starches found in household items like paper, clothing, and glue. While they may crawl on your skin, they do not have the ability to bite or sting. Their mouthparts are designed for chewing, not piercing human skin.
The most common symptoms of silverfish infestations are seeing the insects themselves, finding damage to household items, or seeing their droppings. If you suspect you have a silverfish problem, it's best to take steps to eliminate their food sources and habitats rather than trying to treat 'bites' that don't actually occur.