Your neighbors will soon become aware that you are working at home. Most cities or counties require businesses to be licensed. Some home-operated businesses, however, are not required to have a business license. Check with your local City or County Clerks Office to obtain regulations for your locality. If you are using your own name as your business name it will not need to be registered, but if you use any other name, or even your abbreviated name, almost all localities require that you register the name.
Most states have a name search bureau which is a part of the state government.
You will generally be able to call this office to see if a given name has already been registered to someone else in the state. This is important to do, or it could be costly later. If you give your business a name which is already registered to another company, the other company may demand, and even take legal action, to make sure you comply, that you cease to use the name. Most new businesses are Sole Proprietorships. It is the least complicated.