Lift your head up and look around. I bet there are new people in your workplace.
If so, reach out, say hello, extend a warm welcome. Do something that demonstrates you’re aware of their presence. You might be surprised by the big difference a small gesture can make to a person who is still feeling a little like a fish out of water.
Invite the newcomer to join you for lunch at a favorite spot. From time to time, stop by to say hello and ask how the transition is going. Grab a cup of coffee or tea and take a short stroll together. Introduce him to others. Share what you know about who to go to for what, and how to navigate the formal and informal system. Meet with her to discuss your current projects and how they intersect with hers.
Don’t assume others have handled it. Take the initiative to welcome new colleagues into the fold.