Yes. Once you setup autoresponder > create messages in your particular sequence > you can set up form on your web site.

Your visitors subscribes using the form. They are added to the database. You have an option to add unsubscribe link in outgoing emails. So your subscribers don't want to stay in your list, they will click on the unsubscribe link to remove themselves from the list.

You have an option to receive or not to receive notifications from the script when someone un/subscribes.

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