You can simply use these steps to add your phone number in the Facebook-
-Login to your account
-Go to settings option
-In the left corner choose the "Mobile" option
-Click on "add a phone number"
-Once you enter the mobile number you will get a verification code to confirm the selection.
To remove email follow this step-
-Go to settings
-In the"General tab" click on "Contacts" option
-Click on the "Remove email id" and then click "save changes"