Go to iforgot.apple.com
Enter your Apple ID email address
Follow the on-screen steps to verify your identity
Choose a trusted device or trusted phone number if prompted
Check your trusted device for a verification code
Enter the verification code
Create a new password
Sign in again with your new password on all Apple devices and services
If you cannot access your trusted device or phone number, use account recovery at iforgot.apple.com
If you still cannot reset it, contact Apple Support