Each state offers a CNA education program. You can contact the state aid registry. Each training class costs around $300 and financial aid is available.
Assuming CNA stands for "Cisco Network Associate" you do not need any education, just a book to study for the CNA test and some background in computers and network hardware.
Most CNA licenses can be obtained through training a Nursing home or a local VO-tech school. The training can be from several days to several weeks. The usual education requirement is at least a high school diploma. After the training there is a written and a skills test.