Hi @TusharPalve22 @solace-ken,
Actually, there’s a way of setting DKIM with Cloudflare if you have your own domain. You can sign up free at Cloudflare, then put in your new domain as your new website, wait for all the DNS records to be copied through automatically, and when it says ready you can add that DKIM on Cloudflare DNS.
As far as I can tell, DKIM has nothing to do with recipient spam issues, rather it’s about whether SPF records have been properly setup, up and if the content contains way too many images or links. Business newsletters that are cold-delivered may be an issue for spam.
Have people sign up on your mailing list with double confirmation, email verification can help you keep your domain score clean, this has nothing to do with the hosting of your choice as long as their ASN is a business one. InfinityFree is sponsored by iFastNet which is one of those ASN I have mentioned.
3rd party mailing providers like Zoho and ImrpovMX require DKIM to validate and prevent your domain from being spoofed. DKIM is used to prevent someone else from publishing your domain DNS record and claiming to be you. As these providers do not have control over your domain, this is the best way they could verify requests coming from you. This has nothing to do with email sending or receiving but more a security thing. They can’t just let anyone claiming to be apple.com send emails by the name apple.com, right?
Meanwhile, it is possible to send emails with the PHP mail() function as per this post 4th comment by @Oxy
How do I set up SMTP? - #11, but do honour their restrictions to avoid issues as well.
On a side note, if you intend to use mail() natively on your current hosting, be sure to add an IP allow rule in your SPF record for your non-marketing emails to land in recipients’ inboxes. Your website IP address is located in your client dashboard.
Cheers
-chiucs123.