You cannot view the actual saved email password on an iPhone
Go to Settings
Tap Passwords
Authenticate with Face ID, Touch ID, or passcode
Search for your email account or email provider
Tap the account to view the saved login details
Copy the password if it is shown
If the password is not available, reset it through your email provider
If you only need the email account settings, go to Settings
Tap Mail
Tap Accounts
Select your email account to review the account information