how can an iphone message to other types of phones? hubbys can, but does not

Nobody can send iMessages to non-Apple products. So presumably you’re talking about the ability to send SMS standard text messages.

What is the difference between iMessage and SMS/MMS? - Apple Support

SMS is a cellular carrier function. Seek their assistance.

Well, generally I would say most cellular carriers provide an SMS capability when they provide a voice (telephone) capability. Yours is admittedly an unusual situation. Hopefully you and your husband are set up properly with separate telephone numbers and separate Apple IDs - likely two different telephone numbers on the same cellular carrier account.