What are red flags(not you) when it comes to public settings

I was watching a vid about BW saying that people don't receive them well as introverts in the work place; it reminds of how I am in thought about in classes(I act in certain ways depending on the lecturer), sometimes I am constantly expressing my thoughts and usually I am thought of as (ig???) entertaining to classmates overall, but like tf, it annoys me when people think I will always have something to say, which proves that they think I just be saying shit to rattle on and they don't fucking listen to me. Sometimes when a topic wasn't interesting to me I didn't gaf about the lesson and would sit there(like any normal person would) and people would look back at me like I was about to say a one liner n shit, like i'm fucking bart simpson, tf?(was resisting the urge to not give deaths stares) Or i'm just focusing on my work and the professor starts making conversational gateways with everyone, for me(and someone else opinionated) to set the mood n shit(not my fault yall dead asf and want to roast me for it) But truthfully that's how I usually am irl, I get engaged in the classroom when i'm interested in the lesson but irl I have people forgetting i'm in the freakin room(constantly saying, "I forgot you were here"), in HS I had people thinking I had no friends cuz of how little I would talk with everyone, like bitch, do I look like the circus to you?(side note it also ticks me off because, I only realised cuz I was once told in HS that I was the person saying what everyone wanted to say when no one would). Anyway I'm banking that due to my field I won't have anyone on my ass to be social.