Take lots of notes on things you notice. Build relationships with people. Figure out what they do and what they care about. That way you'll know who to go to wh

Take lots of notes on things you notice. Build relationships with people. Figure out what they do and what they care about. That way you'll know who to go to when you have questions, issues, need favors. Have short intro meetings with lots of people, ideally informal. Lots of coffee. Ask them what challenges they're facing, and what you and your team can do to help them. Consider doing some of those things, especially those things that your manager / team / team lead / etc wants you to do. Ask your manager and co-workers who you should start building relationships with.