How do I resolve issues with sending and receiving text on Messages on iPhone?

I've had some issues with my Message App for a while now, I've been trying to send messages to my family but it keeps saying it wasn't sent and I've tried everything humanly possible, from resetting it, to checking for updates, to even turning off iMessage to see if that would do anything, I've been trying to set up a new google account to replace my old one and it jeeps asking for my phone number to send a code, but sadly i never receive it, in other words i cant send nor can i receive Messages. What can i do?

[Re-Titled by Moderator]

Original Title: I Require Assistance