What torontopharm said, although coming from Pakistan, your first step will be the TOEFL (English equivilancy exam.)
As stated, work visas for pharmacists are currently non-existent (a few places are renewing, but nobody is sponsoring new workers.) If you are not already a legal resident, or able to obtain legal residency via non-work methods (ie family), it is unlikely that you will be able to work in the US as a pharmacist.