How did he communicate with the tribe leaders and such? I learned the Magellan and some of the natives actually worked together and I wonder how did they manage to understand each other.
Magellan was lucky enough to have an interpreter with him when he landed in the Philippines. Back in 1511, Magellan had taken part in the siege of Malacca, a very influential port in the Asian Pacific. During the siege, Magellan acquired slaves like most conquerors do. One of these, was a man named Enrique of Malacca who would sail with Magellan on his voyage to the Philippines. When the crew landed on the Philippines they couldn't understand a single word that the natives said. However, the rulers and elites of the region all spoke Malaccan which of course, Enrique was fluent in. Being so very influential, Malaccan had become the common language of diplomacy and trade in the region. Which was very fortunate for Magellan and his crew.
Magellan's slave, Enrique of Malacca, spoke the Malay language and apparently one or more of the Phillipinos could understand that language.
After Magellan was killed, his will stated that Enrique was to be freed. The remaining officers continued to treat him as a slave. Enrique later betrayed the crew when about 30 of them were massacred at a feast held by the Raja of Cebu.
See - 'Over the Edge of the World: Magellan's Terrifying Circumnavigation of the Globe' by Laurence Bergreen.