You have to get your Pharm.D.(Doctor of Pharmacy) Then you can get licensed to work in that profession. Here is a non-profit site that might be able to help you find more details. http://www.howtobecomeapharmacist.org/
Good luck! :)
Hello Jung: to apply to pharmacy school: Due to the competitiveness, particularly if you want to attend a good pharmacy school with good Pharm D. program, I would recommend to actually obtain a Bachelor of Science degree (prefer biology major or biochemistry major so you can definitely fulfill all "prerequisite science courses"), together with some work experiences in the pharmacy field. For example, University of Southern California School of Pharmacy and University of California, San Francisco School of Pharmacy require a Bachelor of Science degree now, and you also need to pass the interviews. Pharmacy school looks for candidates with a knowledge of the pharmacy profession, so work experiences in the pharmacy field is very crucial. You can work as a pharmacy clerk in retail pharmacy, and that will give you experiences to pass the interviews. A school with good pharmacy program (usually those schools will have good network within the industry) can help you to enroll into strong residency programs upon graduation (not to mention higher chance to pass the licensing exam), and definitely help your professional career in the future. It does not matter where you obtain your Bachelor Degree of Science, but good grade is a must. Good luck!
I'll add onto what Judy mentioned above. You can also do a year or two residency in various fields of pharmacy (inpatient, ambulatory care, community) which gives you more hands on experience just like it is for Medical Doctors. With the number of pharmacy graduates these days, it will give you a leg up on your peers. If you are in the phase of choosing your career, I humbly suggest you shadow and talk to various pharmacist and spend some time with them to see if you really would enjoy being a pharmacist.
First you need to get your core classes out of the way that's your math, science, and English classes (2 years). Then take your PCAT and pass that. The next step is to attend pharmacy school which is about 4 years and get your PharmD. After that take your boards and become licensed in the state you wish to practice.