Q: Want to change incoming email address

Not sure if you want to change the email address on your Mail App or your Apple ID email address. If the former, deleted the account and add a new one following the steps below. If the latter one, try the last two articles.

Set up an email account on your iPhone, iPad, or iPod touch - Apple Support

Change your Apple ID - Apple Support

What to do after you change your Apple ID email address or password - Apple Support

Hi

You may find these support articles helpful, including the instructions for how to keep junk emails from reaching your inbox and for reporting them:

• Identify and filter junk mail in iCloud - Apple Support
• iCloud: Why am I getting junk mail (spam)? - Apple Support