According to the U.S. Bureau of Labor Statistics, nursing aides, also known as nursing assistants, certified nursing assistants, geriatric aides, unlicensed assistive personnel, orderlies, or hospital attendants, provide hands-on care and perform routine tasks under the supervision of nursing and medical staff. Specific tasks vary, with aides handling many aspects of a patient's care. They often help patients eat, dress, and bathe. They also answer calls for help, deliver messages, serve meals, make beds, and tidy up rooms. Aides sometimes are responsible for taking a patient's temperature, pulse rate, respiration rate, or blood pressure. They also may help provide care to patients by helping them get out of bed and walk, escorting them to operating and examining rooms, or providing skin care.
You can find a good overview of the work experiences of CNAs in this document and a list of common, basic daily tasks here and here.