Kindly refer to the following links:
All about night prayers, best time to pray Tahajjud
Duas are answered in the last third of the night
Sleeping before Tahajjud
About Tahajud prayer
Performing the tahajud prayer
How to pray tahajjud
How late can you pray Tahajjud & Witr
Time between Tahajjud & Fajr Prayer
What is the difference between Qyyam Al Layl, Taraweeh and Tahajud
Duas are answered in the last third of the night | Sheikh Assim Al Hakeem
Reciting the Quran loud during night prayer
Should we pray Tahajjud / Night Prayers silently or in a loud voice?
Can we raise our hands and make dua after Tahajjud Prayers?