Enter quietly, learn the room, then speak. The newest person who talks last often gets heard most.

Every room has rules nobody states: what gets taken seriously, who actually decides, which topics are already settled. Talking early means guessing at all of that in public. Waiting costs you a few days of feeling invisible and buys you a first contribution that lands, because it is aimed at something real. People remember the first useful thing you said, not the first thing.

In your first week anywhere, ask more than you assert and note who defers to whom. Find one specific problem nobody has solved. Speak when you have something for that, and keep it short.