Critical reading response paper substance abuse

I’m stuck on a Social Science question and need an explanation.

Demonstrate an understanding of the different classes of substances commonly abused and their physical effects, such as stimulants, depressants, analgesics, THC, etc.; the role of psychotherapeutic medications associated with drug use and withdrawal; explain the following terminologies: therapeutic medications, antidipsotropic, agonist, and antagonist; and demonstrate an understanding of biochemical effects of addictive substances on people’s brains and behavior

the instructions and readings are linked.