Is saying the Shahada enough?

Salam everyone, Just wanted to follow up on my previous post. JazakAllah khair to all who messaged me privately and replied-may Allah bless you all. I've been reflecting on the Shahada and its two parts. The first part, that there is no god but Allah, I've always agreed with that. The second part, that Prophet Muhammad (peace be upon him) is His messenger, I kind of believed but had some doubts. Over the past months, Alhamdulillah, those doubts have been cleared. Now, looking at the full statement, I agree with it completely. But I don't understand how just saying it makes me a Muslim. I feel ready to say it, but I still feel like I wouldn't be a real Muslim-more like an outsider. I can't quite explain it; I agree with the belief, but I don't feel like I belong to the religion, the community, or even connected to Allah. Maybe it's because of my lifestyle and my sins, or something else. I really need some advice again, inshaAllah.