# Son of man
"Son of a human being" or "Son of humanity." God emphasizes that Ezekiel is only a human being. God is eternal and powerful. See Ezekiel 2:1.
# set your face against the mountains of Israel
"stare at the mountains of Israel so that the people there will be harmed". This command to stare at the mountains is a symbol of punishing the people there. See how you translated a similar phrase in Ezekiel 4:3.
# set your face
This refers to attention or gaze.
# the mountains of Israel
"the mountains in the land of Israel"