I cannot play youtube videos using safari

Hello, eyka darla.

Thank you for visiting Apple Support Communities.

I understand that you are experiencing an issue playing YouTube videos via Safari. I would need more information on what exact issue you are experiencing to provide a better answer. However, try clearing all Safari data and test playing a video again.

Clear information from your device

To clear your history and cookies from Safari in iOS 8 or later, tap Settings > Safari > Clear History and Website Data. In iOS 7 or earlier, tap Clear History and tap Clear Cookies and Data.

To clear other stored information from Safari, tap Settings > Safari > Advanced > Website Data > Remove All Website Data.

Safari web settings on your iPhone, iPad, and iPod touch

Also, you may try using the YouTube application which is available via the App Store.

YouTube

Cheers