I will be very grateful if you are able to help me answer this question. I just watched a video from ahlulbayt Q n A youtube saying that our deeds are our responsibilities not the destiny from Allah (Allah's destiny is like our body features, lifespan and so on) How about our job and something like that?
For example, I have been trying to be accepted as an awardee of scholarship, but I got rejected so many times, is it correct if I have this way of thinking "I am so regretful for what I am today, only if I worked harder, I am sure I will be able to get that scholarship" and this way of thinking really stressed me out as if I am the one who decides whether I deserve that scholarship or not, or is it correct to think "this is Allah's destiny, for I am to day is what Allah has decided to me, the fact that I did not study harder, the amount of how much I studied, the fact that I am not that smart (yet), the fact that I chose the wrong topic of essays, are the part of Allah's guidance to this path, this is what's best for me from Allah, maybe I just need to work better to get another scholarship, maybe this program is not suitable for me, and this rejection is His way to tell me, maybe Allah wants me to learn more first before I get the scholarship so that I can survive latar once I get in the program"

There are many aspects of our lives that Allah has decreed. However, we also have a role in making decisions and choosing our fate. As for your case, if you are pursuing something and it’s not happening, try not to be too regretful. It could be the case that it’s not meant for you and Allah has a better plan. So don’t blame yourself. Yes one should work hard and exert reasonable effort. One shouldn’t go to unhealthy extremes to achieve something. Do your part reasonably, leave the rest to Allah and have no regrets.