Integration of Salesforce with Mailchimp

We are setting up Mailchimp to handle automated emails from form submissions. We need to integrate Mailchimp (data and automation rules) with Salesforce. Please see the options for integration (https://www.salesforce.com/solutions/small-business-solutions/integrations/mailchimp-crm-integration/)

We also have some form issues on the website so data being submitted on the form is not going into Salesforce.