How can I help him, please

I think encouragement is important! You said that he didn't get good grades at first, but then he was willing to study hard! Then, you should encourage him more, tell him not to listen to other people's opinions, just work your own, and when the grades come down, we can see the results, and every sentence has many aspects, such as "many people think that it is impossible for him to transform into a good student" This makes him feel a little inferior, but, why can't it be seen as a motivation? ?

The more people don't believe in you, the better you will do, and the potential of people is endless, why can't you succeed?? Others say I can't do it, then I can't?? Others don't have the right to determine my abilities.

Tell him that this may be the result of others seeing his efforts or be jealous, and tell him that no one can decide for himself because he is determined by himself.

You have to talk to him from time to time. It may be better, good students are not judged by others, but obtained by strength, and your friend believes too much in others, tell him that no one can be unselfish! Maybe they're hitting you when they say that!

Tell him! Self-confidence is important! Since I have worked hard to study, I will still have this motivation, don't give up!!

Tell him that people's progress is not for others, but for themselves, and while proving their own value, they need to prove something to others, and don't care too much about other people's opinions, because of this wrong view, the future is likely to be ruined. When talking to him, you might as well use a heavier tone and more rhetorical questions to arouse his awareness of self-reflection, or fighting spirit, and let him think about it for himself.

People have to rely on themselves, and no matter how others help, they only play a supporting role.

But you try to help him, even if it is.

He'll find out later

The sense of accomplishment he needs most now is that if there is something that proves his worth, he can gain confidence from it, so that he can have the confidence to learn. At the same time, you have to keep encouraging and pushing him.

Good students are not judged by others, but obtained by strength.

That's right.

Pull your friend together to help him, slowly build his self-confidence and habit of socializing with others, it should be better.

He is a person with low self-esteem, and especially wants the attention of others, for example, you may be learning for your own development, but he is learning for the affirmation of others, so I suggest that you and your friends around you should care more about him, share your joys, sorrows and sorrows with him, and complete various challenges together, and slowly he will change, a trusting look and a word of affirmation are important to him.