Guide for Integrating FSCF With Mailchimp?

Hello,

I’m attempting to setup a contact form that automatically subscribes people to a mailchimp list who have submitted the contact form. I can’t seem to find a good in-depth guide on how to set this up. I tried the only one that is online here – https://www.isrgrajan.com/how-to-integrate-fs-contact-form-with-mailchimp-in-wordpress.html but I’m still having problems. Any guidance with screenshots would be much appreciated.

Thank you!