[kidlogic]

If you're an individual, form a sole proprietorship (https://www.sba.gov/starting-business/choose-your-business-s...). Just note that, if someone sues you, you are personally liable for any damages.

If you intend to work on projects that carry risk (e.g software that handles a business process that, if fails, costs a client thousands of dollars in damages), opt for a LLC (where your personal finances will be protected from any lawsuits).