Walk in like you belong. Then do the work that proves it.

Confidence by itself gets you through the door and no further, and confidence with nothing behind it turns uncomfortable quickly. The order still matters though. Waiting to feel qualified before you act means never starting, because the feeling is made out of reps, and the reps require walking in first.

Enter the room you feel underqualified for this week anyway. Then be the person who read the material, learned the names, and did the unglamorous part nobody volunteered for. Belonging gets claimed at the door and earned in the weeks after.