Default terms of service is missing

so if I don’t have registered a company to run the forum, then I can’t have terms of service and disclaimers as a person? why only company can have them? What if forum users does something not accepted by public (illegal) and I can’t be liable for their wrong doings? we have to mention it in the site in the form of “Terms of service” to let them that they will be liable for what they post. Eg: acceptable use and content standards.