This is the 14339th most frequent Korean word.
못하면서
"못하면서" means "while not being able to" or "despite being unable to."
The word '못하면서' here is used to express the inability to do homework simultaneously with an action described afterward, 'playing games'.
너는 숙제를 못하면서 게임만 한다.
You only play games while not being able to do your homework.
In this sentence, '못하면서' is showing the simultaneity of the inability to exercise and the effort to maintain health.
운동을 못하면서 건강을 챙기려고 한다.
You try to take care of your health while not being able to exercise.
Here, '못하면서' is describing the action of misunderstanding occurring simultaneously with the inability to speak clearly.