Here's some:
In 2020, during that summer, the Proud Boys engaged in near-daily acts of violence. So much so that the Governor had to declare a state of emergency- https://www.reuters.com/article/us-global-race-protests-portland/oregon-governor-incredibly-worried-about-violence-at-proud-boys-rally-idUSKCN26G2YJ
The Proud Boys leader, Enrique Tario, burned a church. He went to prison for it. https://www-washingtonpost-com.stanford.idm.oclc.org/legal-issues/tarrio-proud-boy-jail-sentence/2021/08/23/df06b84a-041b-11ec-a266-7c7fe02fa374_story.html
They attacked counter protestors in 2018: https://www.thedailybeast.com/nypd-looks-to-charge-9-proud-boys-with-assault-for-manhattan-fight
They started a fight at the first public speech by the founder Gavin Mccinnes. He said, and I quote, "go punch the f*ggots in black hats that won't let us in."
Stanford University has put together a comprehensive look at the Proud Boys, their organization, politics, and all that: https://cisac.fsi.stanford.edu/mappingmilitants/profiles/proud-boys#text_block_32630
The Proud Boys were at the Unite The Right (you know, the one where they chanted The Jews Will Not Replace Us) rally organized by actual Nazis.
They're fascists.