When I Discovered I Was an NPC in an Infinite-Flow World

If Su Qing is another male protagonist, then the author should change the first world. After asking Qi Ren to accompany him in the infirmary for a class, he came back and lied to the teacher that he didn't know Qi Ren was there, causing the teacher to misunderstand that Qi Ren skipped class and punished him by standing still. Also, isn't this world Su Qing's mission world? Why did Qi Ren, the NPC, do the most difficult part of the mission?

I didn't finish the first world, so I felt helpless.