The very wise u/TywinDeVillena has covered this before, [here] (https://www.reddit.com/r/AskHistorians/comments/erm9fy/how_did_the_spanish_conquistadors_and_early/) (I think it's also covered in the FAQ). In short, they took natives often willingly, sometimes by trickery (or by force) back home to learn their language, then used them as translators. While he uses Spanish examples, the British did the same with the most notable examples being Wanchese and Manteo from the Roanoke Expedition of Sir Walter Raleigh, who spent a good bit of time in London allowing study and communication between Algonquin speaking natives and English speaking colonists/explorers. Pocahontas would also travel to London as the Princess of Virginia, dying there a few years later.

It also happened the other way where Europeans were captured or taken by natives and learned their language, then used that knowledge to communicate later, and we find examples in both Spanish history (as linked) and British history. One noteworthy example that deals with the sharing of not just language but also culture was the 1608 exchange of young teenage boys, Namontack for Thomas Savage, happening so soon after Savage arrived from England that Namontack took the same ship back to England. Savage lived with the great Cheif Powhatan, leader of the 30 tribe Tsenacomoco alliance, for three years until late 1610 when he fled back to Jamestown during the first war between the two groups. He would frequently bring messages from Powhatan to Jamestown, and Powhatan had said he purposefully sent Namontack to learn and report back about King James and British culture/motivations in general.