I am trying to get back to eating better this week. My exercise is going well. I have been looking for a few days to figure out how to post activity feed here. To comment on your own page you can use this link
https://community.myfitnesspal.com/en/profile/the_frugal_chef. You have to click the blue button under where it says you can use BBCode in your post. On your page it says add comment. It may say something different on your friends page. To post on your friend's page just change your username with the other person's username.