Ferdinand Magellan ( or ; Portuguese: Fernao de Magalhaes, IPA: [fir'naw di maga'yajS]; Spanish: Fernando de Magallanes, IPA: [fer'nando de maga'yanes]; c. 1480 - 27 April 1521) was a Portuguese explorer who organised the Spanish expedition to the East Indies from 1519 to 1522, resulting in the first circumnavigation of the Earth, completed by Juan Sebastian Elcano. Born into a Portuguese noble family in around 1480, Magellan became a skilled sailor and naval officer and was eventually selected by King Charles I of Spain to search for a westward route to the Maluku Islands (the "Spice Islands"). Commanding a fleet of five vessels, he headed south through the Atlantic Ocean to Patagonia, passing through the Strait of Magellan into a body of water he named the "peaceful sea" (the modern Pacific Ocean).
Departure and crossing of the Atlantic
On 10 August 1519, the five ships under Magellan's command left Seville and descended the Guadalquivir River to Sanlucar de Barrameda, at the mouth of the river. There they remained more than five weeks. Finally they set sail on 20 September 1519 and left Spain.  King Manuel I ordered a Portuguese naval detachment to pursue Magellan, but the explorer evaded them. After stopping at the Canary Islands, Magellan arrived at Cape Verde, where he set course for Cape St. Augustine in Brazil. On 27 November the expedition crossed the equator; on 6 December the crew sighted South America.  On 13 December anchored near present-day Rio de Janeiro. There the crew was resupplied, but bad conditions caused them to delay. Afterwards, they continued to sail south along South America's east coast, looking for the strait that Magellan believed would lead to the Spice Islands. The fleet reached Rio de la Plata in early February, 1520.  For overwintering, Magellan established a temporary settlement called Puerto San Julian on March 30, 1520. On Easter (April 1 and 2), a mutiny broke out involving three of the five ship captains. Magellan took quick and decisive action. Luis de Mendoza, the captain of Victoria, was killed by a party sent by Magellan, and the ship was recovered. After Concepcion's anchor cable had been secretly cut by his forces, the ship drifted towards the well-armed Trinidad, and Concepcion's captain de Quesada and his inner circle surrendered. Juan de Cartagena, the head of the mutineers on the San Antonio, subsequently gave up. Antonio Pigafetta reported that Gaspar Quesada, the captain of Concepcion, and other mutineers were executed, while Juan de Cartagena, the captain of San Antonio, and a priest named Padre Sanchez de la Reina were marooned on the coast. Most of the men, including Juan Sebastian Elcano, were needed and forgiven. Reportedly those killed were drawn and quartered and impaled on the coast; years later, their bones were found by Sir Francis Drake.

Q: where did he leave from?
A: descended the Guadalquivir River to Sanlucar de Barrameda, at the mouth of the river.

Q: when did he leave?
A: Finally they set sail on 20 September 1519 and left Spain.

Q: what was the trip like across the atlantic?
A: There the crew was resupplied, but bad conditions caused them to delay.
what conditions?
unknown
unknown