Outbound mail (SMTP port 25) seems to be blocked by your network. You will not be able to send any mail. Many residential networks block port 25 to prevent hijacked machines from being able to send spam. A quick connection test to Google’s mail server on port 25 failed.
Yes. You CANNOT run MiaB on Google Cloud Platform.
Yes, use literally any VPS provider other than Google Cloud Platform (or Amazon AWS & Microsoft Azure). Avoid these 3 providers and you should be fine.