Lack of fairness in individual life

Hello,
I would be happy if you could share your insights with me regarding the following issue. Ultimately, I think this is a kind of “righteous and evil” clause, and I haven’t really found an explanation that satisfies the mind, and more than the mind, the emotion.
It’s hard for me to understand how a person who has not been fortunate is supposed to feel as a believer. Whether it’s a truly unfortunate person like starving children in Africa, or a person who received a bad education, or a person who has some kind of disorder, or just a person who “didn’t have it easy.” The feeling of “unfairness” screams. The world is not “fair” to the individual at least. Bad things happen to good people, some people tend to be naturally happier than others, etc.
Why wasn’t everyone given an equal opportunity to be satisfied with their situation, weren’t they given the potential to do equally good, to succeed equally. After all, the main test in the world – at least from what I can understand – is what a person does with the choice given to them – good or bad, at any given moment. And if so, why wasn’t everyone given an equal starting point?
(And what is the point of being grateful for what you do have, while there are others who don’t have any of that? It sounds absurd to me to be grateful for things that were given to you while others suffer and were not blessed to receive those same things – there doesn’t seem to be any moral virtue in that, quite the opposite.)
It did occur to me that a thought occurred to me, perhaps it was necessary, that since a person was given a choice, then he could also use it for evil, and therefore he might harm others as well, and yet, if some evil had been done to him, what was his fault, and how would he treat this on the scale of justice on which he believes the world exists? In addition, not all the “unfairness” that exists in the world stems from the evil of other people, people are born into certain conditions that they may never be able to escape from, regardless of the evil of other people, and with certain genetics that limit them as certain boundaries.
In short, a choice was given, as far as I understand, to do good or evil, and if so, it is very difficult for me, emotionally at least, to understand why not every person receives an equal starting point, from which he will be measured from then on. How is a person who did not receive such conditions supposed to encourage himself, and see even in such a thing something valuable, and that even though he did not receive certain things as others, it is still “worthwhile”, and is there any benefit in it?

Thank you very much and have a nice week.