Suggest good smart watch

Looking for something for my dad, should have close to accurate readings and have a long enough battery life (he's bad at keeping stuff charged).

Ideally within 20k. Pls suggest.

I am looking to buy a band or smart watch for my wife

Primary metrics that it should track are below: -steps -sleep time with sleep stages data -Resting heart rate -heart rate variability

I am already using fitbit 4 for the last 2 ye...

Most of the details I’ve added in the title

I want to majorly track my workouts and sleep cycle