I am going to assume you are interested in applying to a pharmacy school in the United States. If that is the case, I can't think of a school in which you NEED pharmacy experience as a prerequisite for admission. Once you are in school you absolutely need professional experience in the field, but again, not to get into school.
Having said that, having work experience in the field, be it paid or volunteer, is certainly a positive in the eyes of admissions. I actually help screen students applying to pharmacy school and I can tell you that work experience and even simply volunteering is certainly beneficial to have on your application.
In terms of you looking for work experience now, the requirements depend on the state in which you want to work. Not all states require technicians to be licensed. New York for example, does not require technicians to be licensed. The company or hospital you work for might, but again it is not a requirement. Retail pharmacies (e.g. Rite Aid, CVS), typically don't require any sort of certification if it is not legally required.
Since you would be applying to schools after you have a degree already, you almost certainly will need to take the PCAT.