Inheritance: A wife and 3 sons

Under Hanafi law the shares are: wife 1/8; sons 7/24 each.

Yes. Pakistani courts apply Islamic inheritance law to Muslims, following the Hanafi school for Sunni Muslims, together with the Muslim Family Laws Ordinance 1961 for grandchildren whose parent died first. Shia families follow Ja’fari rules, which differ.

Funeral expenses, debts (including any unpaid mahr) and any valid will (wasiyyat) of up to one-third to non-heirs. The shares apply to what remains.