iPad pro

Green, means its an SMS/MMS message so either the recipient does not have an internet connection to receive iMessages (blue) or is not an Apple device.

To send messages including pictures to a non Apple device you must have a connected iPhone.

Make sure the iPad has been correctly connected to an iPhone using the same Apple ID, and that Text Message forwarding is turned on for the iPad.

See here for steps: How to forward SMS/MMS text messages from your iPhone to your iPad, iPod touch or Mac - Apple Support

Are you sending the message to another Apple device such as an iPhone or iPad, or to an Android user?

Does your message when sending appear in a blue or in a green bubble?

Deliver to where?

How are you trying to send them?

Please explain in detail what you are doing, so we may be able to help you.