Question

Hello Honorable Rabbi,
I listened to one of the podcasts in which the Rabbi was a guest.
They asked the Rabbi why there is evil/suffering in the world. His answer was that because there is free choice, and because the world operates according to a system of laws that the Holy One, blessed be He, created, if people choose certain paths then they activate certain laws, and that is how evil and suffering come about. God does not intervene in the world, and according to how people choose to act, that is how the results follow, whether for good or for bad. If He were to intervene, then free choice would have no meaning, because every time something bad happened He would fix it, and it would turn out that the world does not operate according to the laws that He Himself established, so what meaning would those laws have? He could simply have refrained from creating the world rather than creating a world that does not operate according to what He Himself determined and changes every time there is evil. (My own note: it could also be that this evil is not really evil, even if it appears evil to us, because in the overall accounting it benefits other people too, even if right now we do not understand how.)
Overall this sounds logical, but the question is: if so, what is the meaning of prayers? If there is a sick person and people pray for him, we are essentially expecting God to change reality for his sake, meaning to intervene in creation. But we said that given a system of laws that He Himself established, He cannot change the game in the middle.
A possible answer could be that when a person prays, through the prayer itself he changes the reality that is subject to laws, and therefore that person can recover. Or for example, if now we increase Torah study and commandments and increase merits, then by doing so we will change reality and then he will have a chance to recover. But this is a bit similar to Haredi claims that advocate increased Torah study when there is a war instead of going out to fight. In the end, the world does work according to nature, so where do prayers / Torah study / increasing merits and the like fit in here?
I would be glad for the Rabbi’s response on the matter.
Thank you in advance
Amir