Made Little Progress in Switching from Google, But Stuck on the root of the problem

Hey everyone!

So, I've made some small progress in switching things up on my Android:

        Replaced  Gmail app with Thunderbird
    Replaced Google Calendar with FOSSify Calendar
    Replaced Google Play Store with Aurora & F-Droid
    Replaced  Android file manager with FOSSify File Manager
    Replaced  Android keyboard with Heliboard

    But now I’m hitting a wall trying to find  ones on root of problem:
    free replacement for Gmail
    free Google Calendar alternative that works well
     on both Android and via Thunderbird    Windows 


  

Self-hosting isn’t really an option for me, so I’d love to hear your suggestions!

If you’ve found something you really like, please share your experiences.

Thanks!

UPDATE

just started a free account with infomaniak so far happy with infomaniak except the free email extensions like @ik.me @etik.com or @ikmail.com addresses whether will be accepted / recognized by institutions like banks etc

also found a community group at https://www.reddit.com/r/Infomaniak/ will search if any group here as well