Does the satisfaction of parents, their praise, and their prayers for their son mean that God is satisfied with him?

There is no way to know that Allah is pleased with a specific servant except through revelation. However, there are many general signs of Allah's pleasure with a servant, among them are Allah's enabling the servant to obey Him and the love people have for him.

Therefore, if a child is dutiful to his parents, their pleasure with him is hoped to be among the signs of Allah's pleasure with him, based on the Prophet's (peace and blessings be upon him) saying: "The pleasure of the Lord is in the pleasure of the parent, and the displeasure of the Lord is in the displeasure of the parent." Thus, a Muslim should strive to be dutiful to his parents and obey Allah seeking His pleasure.