What are the qualifications to be a nurse?

Answer 1

You can still get an asssociates degree in nursing in some states, but that's getting more scarce as the regulatory agencies that oversee the nursing profession are trying to make a B.S. mandatory. After graduating from an accredited school of nursing, you have to sit for, and pass, state boards.
If you're considering applying to a nursing school - check it's accreditation and ask what percentage of their grads passed state boards the first time they took them.

Answer 2

at least an undergraduate degree in nursing and licensure as a registered nurse (RN)