## Yes.
You can turn on Sleep manually on your Apple Watch or on the Health app on your iPhone.

From [Track your sleep with Apple Watch][1] :

> ### Set up Sleep on Apple Watch
> 1. Open the Sleep app  on your Apple Watch.
> 2. Follow the onscreen instructions.
> 
> You can also open the Health app on iPhone, tap Browse, tap Sleep, then tap Get Started (under Set Up Sleep).

**Note** : Your Apple Watch will track your sleep based on the sleep schedule you create or when you manually turn on Sleep Focus. To receive sleep data from Apple Watch, it must track your sleep for at least **4h** each night.


  

[1]: https://support.apple.com/en-gb/guide/watch/apd830528336/8.0/watchos/8.0