iPad pro messaging with Android phones

The only way to message Android devices from an iPad is to have it connected to the iPhone. You have to go to Settings on the iPhone, Settings>Messages>Text Message Forwarding, and select the iPad Pro.

Try turning it off and then on again on the phone and also make sure that your phone number is selected in the Messages settings on the iPad in both places... you can be reached by iMessage at and also Start new conversations from.

You may also want to restart your phone after you turn it off in the phone settings, and then turn it on again after the phone starts up.