How did the first European explorers communicate with the natives in the South Asia, North America, or Africa? How did they get "translators" so quickly? Like, what would they first try to communicate about or say to the natives?
I will give you the case for Christopher Columbus and what the Spanish normally did. As the Spaniards were unable to communicate using regular oral language, they would resort to sign language and gestures, and take people from the land as captives so they could be used as interpreters. Gonzalo Fernández de Oviedo writes this:
Back to our History, having the Admiral arrived to the island of Cuba, where I said, he jumped ashore with some christians, and asked the indians about Cipango. They, making signs, answered and pointed to the isle of Haiti, that we now call Hispaniola. And thinking the indians that the Admiral did not say the name right, they said "Cibao! Cibao!"
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And this Admiral took nine or ten indians with him, so they, as witnesses of his good fortune, would come to kiss the hands of the King and Queen, and would see the lands of the christians, and learn their language, so when they came back here [to the island of Hispaniola] and the christians that were under Goacanagari's protection and in the castle of Puerto Real, would act as translators and interpreters in order to conquer, pacify, and convert these peoples.
Fernández de Oviedo, Gonzalo, General and Natural History of the Indies, Book II, Chapter VI.
Hi, not discouraging other responses here, but you may be interested in this