How do I get my MAC to send/receive text messages and connect with my phone/Apple Watch?

I am signed in with my Apple ID, iMessage is on, and it still won't connect with my phone. I can send SOME messages from my computer, but it won't send "from" my phone number, it sends it from my Apple ID. Also, when I sign in to my Apple ID it is pulling up text messages from 2019 (despite choosing the setting to delete after 1 year), and not any messages from 2021.