Mailchimp

Login to your Mailchimp account

Go to this url - https://admin.mailchimp.com/account/api

And click Create A Key

Give it a name

And click Generate Key

Copy your Key

And click Done

Go back to your mailchimp account

And copy your server prefix from the url

Paste your personal access token on the integrations panel

Click Connected to App

Go back to your mailchimp account

Click Audience dashboard from the sidebar

Click Manage Audience

Then View audiences from the dropdown

Click the dropdown icon beside Stats

Then Settings

Click Audience name and campaign defaults

Copy your list ID or audience ID

Paste these info on the Settings tab

Go to Actions tab

And click the checkboxes you want Then hit Save