Adjusting to new job

I started a new job one month ago. It’s a job that when I accepted it, I thought it was perfect for my skill set and experience. Now I’m beginning to feel like I took on a bigger challenge than I can handle. I was brought on to lead an incredibly strong team that doesn’t seem to want or need a new leader. I know I have value to add, but I’m struggling with how to add it without stepping on the toes of people that have been doing this work for years. I’m worried that my negative thoughts are going to impact what I can achieve here and I want to correct course, but I’m struggling to find positive thoughts that I can believe. Can you help me complete my intentional model?
My unintentional model:
C: Started new job 1 month ago.
T: I’m blowing this.
F: Fear of not being respected by team or boss.
A: Obsess over everything that I think I’ve said or done wrong over past month. Overthink. Don’t speak up.
R: I feel uncomfortable around my team and boss. I don’t take the leadership role that I was hired to fill.

I’d like my intentional model to create confidence, but I’m struggling with a thought that I can actually believe that inspires that feeling.
C: Started new job 1 month ago.
T: ?? (thoughts that I don’t quite believe: I know I add value to this team; I’m exactly where I belong; I know I’m doing the right thing for my team)
F: Confident.
A: Stay positive, look for opportunities to contribute, speak up, make changes I want to see, connect with my team
R: I create space for myself in this organization, I add value to our work.