To use Kiri on Apple Watch, make sure Kiri is installed on your iPhone first, then install the watch app through the Watch app if it does not appear automatically.
Install steps
Install Kiri on your iPhone.
Open the Apple Watch app on your iPhone.
Find Kiri in the available watch apps.
Tap Install if it is not already on the watch.
If you do not see it
Check that your iPhone and Apple Watch both meet the supported software requirements and are properly paired.