Small Centipede in soil

Centipedes are predatorial they will eat other insects and small animals like worms. Millipedes are decomposers, meaning they feed on decaying organic matter. If your soil gets too dry though, or there simply is no organic matter to eat they can feed on living plant roots and they can destroy small seedlings. They will not be able to do significant damage to a mature plant though. If it is some kind of white larvae it might be something else, for example wireworms are also not what you want to have in your soil. A picture would help identifying what youre describing. But if you are sure that it is a centipede no need to worry.