"I can't get out of here" appeared twice in that sentence. The former one meant ability, and the latter meant reality. If they were combined together, that would be what Ning Que was thinking.
The Headmaster of the Academy punished him to retreat into Back Cliff, and that made him feel despondent or even desperate. But he believed that, in the end, the Academy would release him and would not let him remain imprisoned in this cave until death.
However, he was pondering in that cliff cave and started to doubt his judgment in less than one day's time. He thought that perhaps his punishment would be endless.
Hearing his questions, the two people beside the bonfire were silent. Not knowing how much time had passed, the Second Brother shook his head and the Eldest Brother sighed slightly.
The strong mountain wind whistled, and the flames of the bonfire on the cliff platform gradually became smaller.