I recently had to deal with this. I created a free Outlook account. I transferred the domain from Gsuite to cloudflare and signed up for the email beta (all email is forwarded to the Outlook account).

I moved the email using Outlook on Windows (I have a separate MS365 plan for my family so I have access to Outlook). I just connected both accounts to Outlook and then dragged and dropped the emails from the Gsuite account to the Outlook account. Honestly, this was the easiest part of the whole process of leaving Gsuite.

This setup doesn't allow me to send email from the domain, but it does allow me to receive email. It's for a small HOA so I'm fine with this arrangement. If I wanted to send email, then I'd probably sign up for o Microsoft plan that allows me to do that. These are described in other comments.