Moving forward, you'll be using data extensions for all of your subscribers. Unsubscribes work differently in data extensions than lists, so read on for how to deal with unsubscribes.
When you go to send your email using a data extension, make sure you use a publication list. Once you send your email with your combo of data extension and publication list, anyone who unsubscribes will have their unsubscribe stored on the publication list you used. When you go to send an email on the same topic or theme again, the publication list will automatically stop emails from being sent to the people who have previously unsubscribed.
If someone replies to your email asking to unsubscribe, you have two options: tell them to click the unsubscribe link in their original email, or you can do that for them. The link to unsubscribe in their email is paired with their record in the publication list, so it doesn't matter who clicks it.
The Email Framework-Commercial template already contains a link for your constituents to unsubscribe so that you comply with CAN-SPAM policies. As long as you're using the Email Framework, there is no more action needed to edit your email to include an option to unsubscribe.