I’m trying to send messages by using my Apple ID email instead of my number. I went to send and receive everything is set right my iCloud is check and so is my number which I can’t uncheck. I want to be able to receive and send messages using my iCloud just in case I don’t want that person having my number. How can I do this?
Settings → Send & Receive and set ‘Start new conversations from’ to an email address.
The ‘You can be reached by iMessage at’ option has no bearing on what's used for sending messages, so you can ignore the checked options here. The phone number can't be unchecked here as you can always receive messages sent to the phone number of the device.