iPhone 8 and iPad Mini 4 Messages

I have an iPhone 8 and an iPad Mini 4.  Messages sent from my iPad used to appear as if they were sent from my phone.  I recently reset both devices.  Now messages sent from my iPad appear to the recipients as if sent from my email address.  I’m not receiving texts on my iPad unless they’re responses to messages I sent from my iPad.  New texts sent to me are received only on my phone, not my iPad.  How do I set my iPad so messages appear to come from my phone and I receive messages sent to my phone?  I can’t follow online steps because my iPad model doesn’t have the suggested settings.