NPC quests are an optional, additional element, necessary only to get able to use game mechanic supported life elements (e.g. crafting tools).
The main objective is to play with other players.

But to allow all players worldwide to play a common game, they have to talk in a common language. Due to obvious relations of PCs (Silicon Valley) and PC games with the english language, the "Common language" in Yliakum is like english.
Don't be afraid. Your knowledge will be good enough, according to your previous questions. And practicing english in a roleplay is one of the best ways to learn it; many people confirmed this already.
Take your time to get to know the world. Listen to people talking. You will easily find an anchor to join.