Why is the world still racis?

im in 7th grade and im persian today are teacher in math asked me a answer to a question i was answering him and this dude everytime i speaked he kept saying no one cares go bck to ur contery stuiped Mecca person stuiped muslim stop taking no one wants to hear u and rude stuff everytime i taked so i told him the teacher asked me a question and i was answering him and he was like go bck to ur contery and i coudnt ignore all that rude stuff he told me so at lunch my friend asked me wats wrong i coudnt hold bck the tears so bursted out crying and she huged me i told her about how ever since i came her ppl have been racis to me like ur a terrosit and every site i had an account on i had to close it cause ppl were racis and still are and how ppl at school say did they check ur bags twice at the airport cause ur a muslim im just sick and tired of racis ppl wat did i ever do to them its stuiped goverment in IRAN not me! do they think im happy when i hear news that one of my faimly members gets hit by the cops or something dont i have info to deal with my dad is blind and much more in my life is hapening. I hate racis ppl i wish their was peace for every realigon.my point of this question is y is there still racis ppl and how do u deal with them cause im to senstive i would cry if u said ur shirts ugly im just weird like that lol