Looks like you are not a native speaker. That’s ok. Me too. Yet, you have much redundancy in your text and unnecessary references, which is independent of the language. Take the first paragraph for example.
It was around 8 pm. I was sitting in the cafe near to my university like everyday. I was bit exhausted by student's performance in the last test. None of them did well in the test. After the end of the semester, i would be responsible in font of dean for their bad performance. It s not fair, as a professor my job is to teach them ; i cant study for them!
The first sentence you can easily get rid of because it makes no difference whether it was 8 AM, 8.01 AM, 8.10AM or 9.AM The rest of the narrative had no relevancy to that time. Rather than pointing all your mistakes, I’d rather rewrite this paragraph the way I think I could be written.
I was sitting in a cafe next to my university. I was a bit exhausted, by student's performance in the last test. None of them did well. Yet, I am somehow is made responsible for their performance. Is this fair? My job as a professor is to teach them not to study for them!
My advice for you is to install Grammarly on your computer. It’s free and it is very helpful.
I am not a native speaker and didnt write so many story in english. I will use Grammarly on my computer soon. Thank you for feedback.