It can be a little confusing trying to figure it out. The "Follow" "Following" button is at the top of a Support Group for example Heart Rhythm Conditions and the small bell icon at the bottom of a discussion description is used to select how you want to be notified. Another way to select the support groups you follow is through your Profile Settings & Preferences. You can access this by clicking on your profile icon at the top right of any page and select Settings & Preferences. Then scroll down to the Notifications and Preferences section and click the Edit link to the right of Activity I Have Followed or Muted. This will show you the groups you follow or have muted (unchecked).

Let me know if you still have a question and I'll see if I can help.