How do I add a photo to a status?

You can't add a photo on the web version only on the app.

On the app there is a little camera icon next to the "Share Something" (at least there is on Android).

If it's not working for you, check you have given MFP permission for your camera and files.

This is a real mystery - some people on my feed freely post photos. Others cannot. I'm one of the ones that cannot. I have a laptop and an iPhone. It's the most primitive photo posting application I've ever seen. Why MFP insists on making posting photos - something that is so incredibly simple everywhere, so difficult is beyond me.