In order not to miss Fajr prayer due to sleep, you should sleep early. Also use the alarm clock and cooperate with your family on this matter. Always ask Allah to help you and guide you.

1- The time for Fajr prayer lasts from the onset of the true dawn until the sun starts to rise. 2- Delaying the Fajr prayer beyond its proper time with no excuse is a major sin

Prayer offered before its time is not valid, according to the consensus of the Muslims. If a person offers a prayer before its time deliberately, the prayer is invalid. If that was not done deliberately, then it is not a sin and his prayer is regarded as nafl.

There is nothing wrong with delaying `Isha’ prayer in Ramadan on condition that the Imam does not delay the prayer so much that he causes hardship to the members of the congregation.