The quick answer to this is no you don’t, there is no such license that exists. However, to purchase the chemicals you will be asked to prove your intended use of the chemical and that it will only be used in a professional manner under a business. Along with this to abide by HSE regulations, the chemicals must be used within their label compliance i.e. a bleaching agent stating to be used for exterior cleaning to then be used for exactly that and nothing else. So no there is no license however they are controlled substances that are not readily available to the public and will only be sold to professionals.