Resources for Learning Email Deliverability and Self-Setup Tips

Hi all, does anyone have resources they can suggest to learn about email deliverability and setting up email accounts for outbound campaigns yourself? I tried via Instantly but I got this message after 4 weeks of warming up DFY accounts: "Thanks for the wait. Your DFY accounts were impacted by a recent automated suspension sweep from Google. These sweeps sometimes occur, even when there’s no issue or policy violation on your side." They are going to replace the emails with a new domain at no charge but I need to go back through the warm up process. I'm looking for information on how not to rely on 3rd parties for this to so I can prevent this from happening again.