Tracking device

Hello! I’ve been thinking about getting a device to help with heart rate, calories burned, etc and I’m wondering if anyone has any input on which one is a good buy. I’m pretty sure I want a Fitbit but I know there are other options out there. And even with a Fitbit, there are several to choose from...it’s overwhelming my brain!🤪 I don’t need a gps or any kind of mail or phone capability. Mainly I want it for heart rate, calories burned, and sleep monitoring.

Thanks in advance for your suggestions!