This wikiHow teaches you how to display a phone number in iMessage if you have a new number, as well as how to choose an email address as the point of sending messages instead of a phone number. Unfortunately, you can't use a phone number other than the number installed on your iPhone in iMessage.
Step
Method 1 of 2: Reset Phone Number
Step 1. Understand when this method can be followed
A phone number reset on iPhone is only needed if the number shown in the iMessage segment is not correct. If the device is already sending iMessage messages by phone number, skip this method.
You can set your email address as the point of delivery for iMessage messages if you don't want others to see your phone number in iMessage
Step 2. Open the device settings menu
(“Settings”).
Tap the “Settings” icon which looks like a gray box with gears.
Step 3. Swipe screen and touch
"Messages".
This option is near the bottom half of the “Settings” page.
Step 4. Touch the green “iMessage” switch
This switch is at the top of the page. After that, the iMessages feature will be temporarily disabled on the iPhone.
Step 5. Turn off iPhone and wait for 10 minutes
Press and hold the power button on the right side of the device, then slide the switch “ Power ”
on the "slide to power off" track to the right. After the device turns off, wait for at least 10 minutes before proceeding to the next step.
You can also press the power button five times to display the power menu
Step 6. Restart the device
After 10 minutes, press and hold the device's power button until you see the Apple logo on the screen. After that, release the button and wait for the iPhone to turn on again.
If you apply a passcode, enter the code before continuing
Step 7. Re-enable the iMessage feature
open
“ Settings ", touch " Messages ”, touch the white " iMessage " switch
and wait for the message " Waiting for activation… " to disappear under the " iMessage " section.
Step 8. Check the displayed phone number
After iMessage is active again, you can check the accuracy of the iMessage phone number by touching the “ Send & Receive ” at the bottom of the screen and make sure the number displayed at the top of the screen is the currently active number.
If you still don't see the phone number at the top of the screen, repeat this method. Make sure you wait for at least 10 minutes before turning on the device again
Method 2 of 2: Changing iMessage Messaging Location
Step 1. Open the device settings menu
(“Settings”).
Tap the “Settings” icon which looks like a set of gears on a gray background.
Step 2. Swipe the screen and touch
"Messages".
This option is in the middle of the “Settings” page.
Step 3. Touch Send & Receive
This option is at the bottom of the screen.
You may need to swipe to see the options, depending on the screen size of the device
Step 4. Review the “START NEW CONVERSATIONS FROM” segment
This segment is at the bottom of the page and shows every address that can be used to send an iMessage message.
At least you'll see one email address and one phone number. It's an Apple ID email address
Step 5. Select an email address
Touch the address you want to use to send the iMessage message. That way, when you send an iMessage message, the recipient will get it from your email address, not a phone number.