I suggest, noclue, that you read several reviews of Zoho Mail. Here's a good one:
https://reviews.financesonline.com/p/zoho-mail/
To see other reviews, google "zoho mail reviews" (without the quotes).
For receiving your newsletters, a free Zoho Mail account should be fine. But there's only one way to know for sure: Get an account, try it out, and see if your newsletters arrive in your Zoho Mail Inbox.