Which fitness smartwatch is the most accurate?

Hello, I'm looking for a fitness watch that can track my fitness data, such as steps, calories burned, and heart rate. I've often read that the Apple Watch has a significant deviation from the actual data. Even apart from that, I find it very expensive and can't afford it. I can certainly imagine that a deviation is possible, but which fitness watch tracks the data as accurately as possible? It would also be good if it wasn't too expensive.