Short answers, pulled from the story.
Ahmad Shah Durrani's forces occupied and looted the Mughal capital of Delhi from the 28th of January to the 22nd of February 1757. Contemporary writers estimated the total plunder at anywhere from 30 to 300 million rupees.
Ahmad Shah Durrani, founder of the Durrani Empire and based in Kandahar, led the Afghan forces. It was his fourth invasion of India, launched with an army of 80,000 men in November 1756.
Ahmad Shah was invited to invade by multiple parties. Mughlani Begum, the deposed administrator of Punjab, promised him wealth, while Najib ud-Daula, a chief of Rohilkand, and Mughal emperor Alamgir II sent their own requests.
Ahmad Shah imposed taxes on every household, ordered Hindus to wear distinctive marks, and subjected those suspected of hiding valuables to torture. The vizier Imad ul-Mulk was forced to surrender 10 million rupees plus 300,000 gold coins. An elderly woman named Sholapuri Begum was threatened with iron pins until she revealed the location of a buried fortune that yielded more than 15 million rupees in cash.
The Bengal Subah's best forces were diverted to fight the Afghans, leaving them weakened. Within months of Ahmad Shah's departure, that depleted army was defeated by the British at the Battle of Plassey, beginning British dominance in India.
Contemporary writers disputed the total, with estimates ranging from 30 to 300 million rupees. Over 28,000 elephants, camels, and mules were needed to carry the spoils. Many of Ahmad Shah's cavalry returned to Afghanistan on foot, having loaded their horses with personal plunder.