I set up my iPhone with a wrong email

Hello Mha22blue,

Welcome to Apple Support Communities. It sounds like you are signed in to your iPhone using the wrong Apple ID. Right?

If so, you can sign out using the guidance below from Sign out of iCloud on your iPhone, iPad, iPod touch, Apple TV, or Mac - Apple Support.

"Sign out on your iPhone, iPad, or iPod touch

1. Go to Settings > [your name]. 
2. Scroll down to the bottom.
3. Tap Sign Out.
4. Enter your Apple ID password and tap Turn Off. Forgot your Apple ID password? 
5. Turn on the data that you want to keep a copy of on your device.
6. Tap Sign Out.
7. Tap Sign Out again to confirm that you want to sign out of iCloud."

You'll then be able to sign in with the correct Apple ID and enable Mail.

If you need to create a new Apple ID, you can use the guidance from How to create a new Apple ID - Apple Support.

Kind regards.

Sign out existing Apple ID signed in say example1@gmail.com from iPhone Sign out of iCloud on your iPhone, iPad, iPod touch, Apple TV, or Mac - Apple Support

You have to remove the Apple ID from pop screen that appear and click on option create a new Apple ID this time the Apple ID should be example2@icloud.com How to create a new Apple ID - Apple Support

Make you must have Apple ID password , three answers for respective questions , date of birth , rescue mail address and its password in your records before signing out the primary Apple ID address as they will be required in upcoming steps to create a new Apple ID .