The economic actor — the entity that performs all economic decisions and actions — is the individual.
A given individual may assume a variety of economic roles during their life or may specialize in one or more roles: as a consumer, as a producer, as a financier, as an employee or laborer, as a manager, and most importantly as an entrepreneur/capitalist, etc.
All organizations are groups of individuals. All organizations — shops, unions, businesses, corporations, nations, etc. — are an organized group of individuals in specific roles with specific relationships and responsibilities. In all such cases, it is individuals who are making the decisions and taking action, either individually or in coordination with other individuals based on their hierarchical roles and responsibilities.