In brief, what are the times when prayers are answered and how should one pray, what are the characteristics of a person whose prayers are answered, what are the formulas for prayer, and is intercession considered a prayer?

For a supplication (dua) to be accepted, there are conditions, impediments, and reasons. Its conditions are three: supplicating Allah alone with sincerity and devotion, not supplicating for a sin or the severance of kinship ties, and supplicating with an attentive heart, certain of the response. The impediments are the opposite of these conditions. The reasons for acceptance are: beginning the supplication with praise of Allah and sending blessings upon the Prophet (peace be upon him), raising the hands, not hesitating, seeking out times of acceptance, consuming lawful provisions, and avoiding unlawful things. As for the manner of supplication: it begins with praise of Allah and sending blessings upon the Prophet (peace be upon him), having an attentive heart, having good expectations of Allah, being certain of the response, and supplicating for one's needs, both good in this world and the Hereafter. It is permissible to ask Allah directly for one's needs or to use a legitimate means, such as seeking intercession through Allah's names and attributes, through righteous deeds, or through the supplication of a living righteous person. As for seeking intercession through the prestige of the Prophet (peace be upon him) and the righteous, there is a difference of opinion, and the preponderant view is that it is forbidden.