I have written before about encrypted email provider Proton Mail. In fact, I used Proton Mail last week when I was in China as it was the only email service I could find that was not blocked by the Great Firewall of China. (I bet that changes soon!) Now the government of Turkey isn’t allowing its citizens access to the privacy-enabled email service.
See https://protonmail.com/blog/turkey-online-censorship-bypass/ for the details, unless you are in Turkey in which case the article is blocked.