How do I change my SMS NUMBER.?

Hello Kmansur,

It sounds like you are wanting to change the phone number you entered to receive SMS messages from iCloud Keychain. The following article should help you do that named:

iCloud: Troubleshooting iCloud Keychain

http://support.apple.com/kb/TS4644

• Check that you have the correct phone number associated with your account:
  • Devices using iOS 7.0.3 or later: Tap Settings > iCloud > Account, then tap Keychain. Check that the phone number listed under Verification Number is correct. If not, enter another phone number.
  • Macs using OS X Mavericks v10.9 or later: Choose Apple () menu > System Preferences. Click iCloud, then click Account Details. Check that the phone number listed under Verification number is correct. If not, enter another phone number.
• Check Apple System Status to see if there is currently a service outage affecting iCloud Keychain.
• If you do not have access to a device that has iCloud Keychain enabled, you can contact Apple Support and verify your identity for help completing iCloud Keychain setup.

Thank you for using Apple Support Communities.

All the best,

Sterling

this is stupid, no telephone number listed what so ever