To attain the full reward of Laylat al-Qadr, is it a condition to pray the entire night, or is part of it sufficient, and what is meant by "Qiyam Laylat al-Qadr" (praying during the night of Qadr) in the Hadith?

The reward for observing Laylat al-Qadr (the Night of Decree) is immense, as the Prophet, peace and blessings be upon him, said: "Whoever stands (in prayer) during Laylat al-Qadr with faith and hoping for Allah’s reward, will have all of his past sins forgiven." Observing Laylat al-Qadr can be achieved by observing part of it, or by performing some acts of obedience such as studying Islamic knowledge, reciting the Qur’an, praying, or engaging in remembrance (dhikr). It is not a condition to observe the entire night.