To change the password for Gmail, you must change the password for your Google account.
1.Enter to Google and click on your profile account in the right corner of the screen.
2. Then click on “Manage your Google Account”
3. In the Google Account page search “password” in the search bar. And click on “Password” in the results popup window.
4. Maybe google ask you to put your google password before you gonna change the password. And then you move to create new password.
5. Now Enter you new password and type again the new password and click “Change password” and That’s all!