To change your display name on YouTube, you can follow these steps:
1. Sign in to your account.
2. Go to Settings.
3. Click on Edit on Google next to your username.
4. Update the YouTube username and click OK.
Alternatively, you can:
1. Sign in to YouTube Studio.
2. Go to Customization and Basic info.
3. Add whatever channel name you like!
You can change your name twice every 14 days. I hope this helps!