Unless you really need to work, I would suggest holding off until the 2nd semester of Nursing school. I had zero medical background and was working in retail when I started Nursing school last Fall. I just worked part time at that job during the first semester.
They teach you the basics of patient care in school and you are eased into it pretty well in the first clinical. After that first semester, you can get a job as a nurse extern, student nurse tech, or student nurse associate. All will be really flexible with your class schedule and all pay well (more than a CNA, and you get to do more)
Also, because CNA's are certified, I imagine you would have to pay money for the class. Probably not worth it, because before you know it you will be learning it in nursing school, and trust me, by the time you are done with the first year, those CNA type duties will be the last thing on your mind!! You will be trying to pass some tests on very intense information.
Good luck to you,

Jillian
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