How do you connect your iPhone to AirTags?

Do you mean AirTags?

See this instructions to set them up

1. Make sure your device is ready for setup.
2. If your AirTag is new, remove the wrap around the product and pull out the tab to activate the battery. Your AirTag will play a sound.
3. Hold your AirTag near your iPhone, iPad or iPod touch, then tap Connect.* If you have multiple AirTags and see “More than one AirTag detected”, make sure only one AirTag is near your device at one time. Need help with connecting your AirTag? 
4. Select an item name from the list, or select Custom Name to name your AirTag and choose an emoji. Then tap Continue.
5. To register your AirTag with your Apple ID, tap Continue again. 
6. Tap Done. 

Now, you can attach your AirTag to your item and see it in the Find My app. 

If you still cannot set up your AirTag after following these instructions, see this

1. Make sure your device is ready for setup.
2. If the setup animation has disappeared, press the side button or Sleep/Wake button on your iPhone to put your device to sleep. Then wake and unlock your iPhone. Wait up to 15 seconds, and the animation should reappear. 
3. If you have multiple AirTags to set up, make sure only one is near your device at one time.
4. Remove and then replace the battery in your AirTag.* 
5. If your AirTag still won’t connect to your device, reset your AirTag. 

Find out what to do if you see a message that says the AirTag is connected to another Apple ID.