Can praying to god/deity help a person attain something if that is not present in their Destiny/Prarabdha?
If it is not present in your destiny/prarabdha and you pray for it like you really want it, can you get it?
Narada said: "Satyavana is going to die within a year."
Narada then said, 'He hath one only defect that hath overwhelmed all his virtues. That defect is incapable of being conquered by even the greatest efforts. He hath only one defect, and no other. Within a year from this day, Satyavan, endued with a short life will cast off his body!'
What was done to change Satyavana's destiny?
When only four days of the appointed life span were left,Savitri observed a religious rite that has now become famous savitri vrata. Amongst other things, this involved fasting for a period of three days.
And having ascertained that her husband would die on the fourth day following, the damsel fasted day and night, observing the Triratra vow (fast for three day-nights together).
Finally, how Savitri got Satyavana's life back from Yama?
On Forth day, Satyavana went to collect fodder, roots and fruits in the dense part of the forest and Savitri also accompanied her husband. When they were tired, Savitri sat down beside a pond to rest. Satyavana continued to collect fodder and firewood near the pond. While he was thus engaged, he started to suffer from a splitting headache. "Savitri," he said, "I cannot bear this pain any longer. Let me rest for a while with my head in your lap."
While Satyavana was resting with his head on Savitri's lap, Yama arrived to claim Satyavana. Yama's complexion was dark and he was dressed entirely in yellow. His crown was golden. Armlets graced his arms and necklaces hung around his neck. In each human body there is an entity that is only the size of a finger in length. This is the part of the body that is claimed by Yama and taken to his abode.
When this is done, only the dead body is left. Yama tied up Satyavana's minute body in a noose and prepared to take it to his abode. But when Yama left, Savitri followed him.
"Where do you think you are going?" asked Yama.
"I am following my husband," replied Savitri.
"There is no greater duty for a wife than serving her husband. Since my husband is leaving, I have to leave with him."
"I am pleased at your devotion," said Yama. "Ask for a boon and I shall grant it to you. The only thing that you cannot ask for is that Satyavana be brought back to life."
"My father-in-law has become blind," replied Saviti. "He can therefore no longer be the king. Please grant me the boon that his eyesight is restored so that he can become the king again." "I grant you that." Said Yama. "Now please return. You will unnecessarily get tired if you follow me."
"How I can get tired if I follow you?" asked Savitri. "You are the chief of all the gods. Is it possible to get tired if one follows you?"
"That pleases me even more," said Yama. "Ask for another boon. But under no circumstances are you allowed to ask that Satyavana be brought back to life." "My father has no sons," replied Savitri. "Please grant me the boon that he may have a hundred sons." "I grant you that," said Yama. "Now return. Go and perform your husband's funeral rites. Serve your parents and parents-in-law well. You are unnecessarily tiring yourself by following me around."
"I thank you for your advice." Replied Savitri. "But I have already told you that I cannot possibly get tired. You are the lord of dharma, the lord of righteousness. Can one possibly tire oneself by following such a person?"
"Your devotion is truly amazing, Ask for another boon. But do not ask for Satyavana's life." "Please grant me the boon that Satyavana and I may have a hundred sons," requested Savitri. Yama granted the boon without thinking and Savitri then pointed out that what Yama had agreed to would be impossible if Satyavana died. Yama had no option but to restore Satyavana to life. Yama blessed Savitri and went away.
In due course, Satyavana and Savitri had a hundred sons named that Malvas. Savitri is a model for all devoted wives to follow. (-This narration is from Matsya Purana, this can also be read from Mahabharata)