You're held to the scope of practice of the job that you are working. If you work as a CNA, you must work within that scope and not even once try to work outside of that. If you work as an RN then that's your scope. I've worked my way up from CNA to LVN to RN and I can tell you that having that experience behind me adds to my level of confidence. So it may help you to work as a CNA for a bit, it may also help you to get your next RN job too.