describes himself as a hunter pursuing a deer he has no hope of catching. That's a metaphoric way of describing his desire for a woman who isn't interested in him because she has already committed herself to another man. I'd say that the conflict in that poem is between the man's desire to win the woman and her desire not to be won. Without that conflict, there would be no poem.
Something that is in high supply could be something like toilet paper during this pandemic. Something in low demand could be something that the majority of people dont use as often.