Change the Email Address
Step 1: Click the avatar on the top right corner and go to "My Account". 
Step 2: Select "Personal Info" > Email Address >Modify an Email >Enter "Captcha" 

Step 3: Click "Send Verification Code" to your current email address , enter the verification code in the emaill,click " Confirm" 
Step 4: Enter a new email address > Enter a "Captcha" > Enter the captcha in the email > Click " Confirm"

Change the Password
Step 1: Click the avtar on the upper right corner of the page and select "My Account". 
Step 2: Select "Personal Info" > select "Password" > "Reset the password" > enter Current password and New password in order 

Step 3: Finally, enter your password again > Click "Confirm"