how do i deal with fear of being laughed at?

how do i deal with fear of being laughed at? I dont like when people think I'm a kill joy or think im clumsy or funny when im trying not to be.I guess I have this fear because i got bullied in school, and i still haven't gotten over it because it happened for so long. I got laughed at and people pretended i was stupid. I just hate being mocked. i hate having people bring me down. i need to be stronger emotionally i need self acceptance.But i dont know how to do that. I need confidence. I can kind of laugh at myself if im around people that wont mock me that i know will be nice to me and are laughing at the situation not at me. the kids that bullied me talked slow and pretend like I still did not understand, and the worst insult to me is being dumb, i was in english as a second language because English is my second language and kids bullied me for that, they said only stupid people go there and you will never be smart.I feel like no matter what i do i cant be smart, i am getting a bachelors degree, i feel like i have memorized most of the dictionary, jk not really but i know alot of complicated things like the krebs cycle and have memorized molecules like ribulosebiphosphatecarboxylaceoxegenace.I cant convince myself that i am smart. i dont really know if i am smart or not but i do not feel that way compared to others.I want to be around people that are into science like chemistry and biology, i just do not know where to find them, at least ones that are interested in being friends with me and find time for me. I dont have social anxiety by the way. i love to be around people and talk to people. sorry this got way off topic.