Click on this link to learn how to change your Apple ID password --> Change your Apple ID password - Apple Support or Change your Apple ID password - Apple Support
This is how you change your Apple ID password on your iPhone, iPad, iPod touch, or Apple Watch:
1. Tap Settings > your name > Password & Security.
2. Tap Change Password.
3. Enter your current password or device passcode, then enter a new password and confirm the new password.
Forgot your password? Go to --> If you forgot your Apple ID password - Apple Support
4. Tap Change or Change Password.