I lost my Apple TV remote how can I use my apple tv?

Try these troubleshooting tips:

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If you lost the remote for your Apple TV

You can control your Apple TV with your iPhone, iPad, or iPod touch, or you can use a different remote.

Use the Apple TV Remote in Control Center

If you lost the remote for your Apple TV 4K or Apple TV HD, set up and use the Apple TV Remote on your iPhone, iPad, or iPod touch.

Use a different remote

• If you have an Apple TV 4K or Apple TV HD, you can use a Siri Remote (1st and 2nd generation), an Apple TV Remote (1st and 2nd generation), or an Apple Remote.
• If you have an Apple TV (3rd generation), you need to use an Apple Remote. 

You can buy a new remote for your Apple TV from the Apple Online Store, Apple Store, or other retailer. Or find out how to use a network-based remote with your Apple TV. 

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copied from: If you lost the remote for your Apple TV - Apple Support

To be honest the smartest thing to do is find or replace the original remote. Apple sells them or you can find them on Amazon too.

Best of luck!