@mariana4you can find settings page if you look into upper right corner of your screen, click on your username and go to 'settings'. Here is direct link to this page - click. Here you will be able to upload a picture/photo after you have had some website activity, and I apologize for not having a clear answer on this, but I will look it up and post after I find exact information!
As others already explained, members are currently unable to put any more info in a form of text 'About me' description on their profiles, and there are few reasons, most important of which is preserving safety, anonymity, confidentiality and also because it is hard to monitor and report inappropriate content. It also helps distinguish listener and member roles on this website better and preserve boundaries, because the main purpose of this website is to offer help and support to people in need, and socialization is not among top priorities. I hope this explained a bit.
I wish you a wonderful day and hope this was helpful!