When does the time for the Fajr prayer begin?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
The time for the Fajr prayer begins once the Mu’adhin starts the second Adhan (Al-Adhan al-Thani), and not after the first Adhan. And Allah the Exalted knows best.
Is it permissible to purchase the Udhiyah on installments?
It is permissible to purchase the sacrificial animal (uḍḥiyyah) on installments or by borrowing its price. However, it is not recommended for the poor to do so, because they are not required to offer a sacrifice, and Allah does not burden a soul beyond its capacity. If doing so would lead to negligence in providing for one's dependents (nafaqah wājibah), then giving precedence to obligatory maintenance over borrowing to buy the sacrifice is appropriate. This is based on the saying of the Prophet (peace and blessings be upon him): "It is sufficient sin for a person to withhold food from those whom he is responsible to support."
Furthermore, the sacrifice is valid from one who has a debt, but it is preferable (awlā) to repay the debt first, especially if the debt is due immediately (ḥāll). And Allah Almighty knows best.
When is Istikharah (guidance prayer) Du`a offered, before Tasleem (saying asalamu alikum warahmatu allah wa barakatuh to end the prayer), or after it?
It is offered after Tasleem.
What is the Islamic punishment for the one who neglects prayer?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
Neglecting the prayer (Salah) is among the major sins (Al-Kaba’ir). One who neglects it out of laziness is considered a transgresor (Fasiq), while one who neglects it while denying its obligation is a disbeliever (Kafir). And Allah the Exalted knows best.