What is the reason for the feeling that Allah is angry and that this world is torment, and that prayers for a deceased mother do not reach her, despite performing prayers, fasting, and reading the Quran?

Everything that afflicts a servant is by the divine decree that Allah wrote fifty thousand years before He created the heavens and the earth. He executes these decrees with His wisdom and vast mercy, for He is more merciful to His servants and more knowledgeable of what is best for them. This is affirmed by His saying, the Almighty: "But perhaps you hate a thing and it is good for you; and perhaps you love a thing and it is bad for you. And Allah knows, while you know not." Tribulation is not a sign of Allah's wrath; rather, it may be a sign of His love. It was narrated from Anas that the Prophet, peace and blessings be upon him, said: "Indeed, the greatness of the reward is with the greatness of the tribulation. And indeed, when Allah loves a people, He afflicts them. So, whoever is pleased, for him is pleasure; and whoever is displeased, for him is displeasure." Supplication is beneficial in all circumstances, for there is no Muslim who makes a supplication but Allah grants him one of three things: either He hastens his supplication for him, or He stores it for him in the Hereafter, or He averts from him an evil equivalent to it.