pharmacyThey all have the same meaning and are interchangeable. When I get my prescription, I say I'm going to the chemists or the pharmacy. I think drugstore is commonly said in America, I have.
Chemists's is the possessive, in shortened form, for chemist's + shop. (“Chemists's shop” is shortened to “chemist's) You may choose either word, when you mean you are going to Boots.
chemist's shopthey all mean the same thing (a shop that sells medicine and other things) but “pharmacy” is normally used when the shop only sells medicine. a drugstore/ chemists shop is normally used.
