Im scared of waterslides?

Tommorow im going to the waterpark with my family and one of my friends and i not the kind of person who likes rollercoasters and waterslides all that much but i wanna change that. I am a big scaredy cat and i still dont know how to swim(im 13) yea i know thats really really stupid of a 13 year old that doesnt know how to swim but hey when i was little i didnt even wanna get in a pool so it was really hard for my family to teach me to swim and its really embarrasing becuase i dont wanna have to tell my friend that i dont know how to swim , anyways thats basically why im so scared to get on waterslides, and also becuase i am obviously a scaredy cat, but i wanna change that and i am wondering if any of you people can give me any tips on how to not be scared to get on waterslides?? It would really mean a lot and thanx for reading my question, and please please pleeeaase no mean comments, because thats been getting really annoying lately, hope you understand :)