What is the ruling on the vow made by the questioner to abandon prayer, and is it permissible to give the vowed money to her brother or relatives instead of orphans, given that there are no orphans in her family?

We hope that Allah keeps the whispers of Shaytan away from you and grants you well-being. To get rid of the whispers of Shaytan, seek refuge in Allah and occupy yourself with the causes of humility (khushu'), and recite the two Mu'awwidhatayn (Surahs Al-Falaq and An-Nas) morning and evening. The Prophet, peace and blessings be upon him, guided Uthman ibn Abi al-'As, when he felt whispers during prayer, to seek refuge in Allah and to spit lightly to his left three times.

As for vows (nathr), the original ruling is that they must be fulfilled, as the Prophet, peace and blessings be upon him, said: "Whoever vows to obey Allah, let him obey Him." What you did is a "nathr al-lajaj" (a vow of contention or anger), which is like an oath intended to prevent oneself from doing something or to urge oneself to do something. It is not obligatory to fulfill it, and one may offer an expiation for an oath (kaffarat yamin), which is: feeding ten poor persons, or clothing them, or freeing a slave. If one cannot find any of these, then fasting for three days.

And know that abandoning prayer is among the greatest major sins.