Press the button on the Airpods Tracker and you will see blue LED light up for 3 seconds. This means that Airpods Tracker is turned on.
Go to Assistant Trigger app and click "Configure Tracker"
It will scan for Airpods Tracker device and click "OK" once it finds it.
Then you will see Airpods Tracker information. Just connect Airpods and you will see battery level.