quick eng reminder: who functions as a subject, while whom functions as an object

use who when the word is performing the action. (pronouns to answer such qns: she, he, etc)

use whom when it is receiving the action. (pronouns to answer such qns: him, her, etc)

who (e.g.)
who is getting the cheese?
who are you?

whom (e.g.)
whom does this belong to?
whom are you talking to?
#note