Are there any smartwatches out there with basic functions (time, timer, sleep time, steps taken) that work as a standalone device, without having to use a smartphone?
[1] https://www.amazon.com/Pedometer-Walking-Counter-Removable-A...
You can also get a pedometer + digital watch for $10.
[2] https://www.amazon.com/Pedometer-Walking-Waterproof-Calories...
For sleep tracking, there are various phone apps that you can leave on your bed at night. I used one for years that synced via iCloud rather than some janky fitness account.