I'm not sure what you are doing.   There is no "choose file" function.  To add a photo of a family member, click on the [Add photo of Xxxxx] button on the upper left, under the members name.  Then click on the [Browse...] button to bring up the file selector.  Navigate to and select the desired photo and click [Open] then the [Upload] button.  To change the photo click on the photo on the left panel and do the same dance.