Notice the news caption under the photo. This is the most used photo to substantiate the alleged “riot.”
This is NOT a riot. Clearly, these people are not storming the Capitol. They are looking over the railing at the people below. Moreover, we don’t know if these are Trump supporters or not. While whatever this is was occurring, Trump was still speaking to the rally a long distance away.
Whatever this photo is, it is not evidence of a riot.
Before the riot took place Trump held a rally where he encouraged his suporters to walk to the Capitol. A view of his supporters scaling the west wall of the US Capitol on January 6
Here is a humorous explanation of the non-riot: https://www.unz.com/chopkins/thats-all-folks/