Solution Steps

1. Go to myaccount.google.com and sign in.
2. Click "Data & privacy" → "Delete a Google service".
3. Select "YouTube" and follow the prompts.
4. Or go to youtube.com → Settings → Advanced settings → Delete channel.
5. To delete entire Google account: "Data & privacy" → "Delete your Google Account".
6. Download your data before deletion (takeout.google.com).
7. Confirm deletion by entering your password.