Struggling with Diet and Exercise

hello! sooo i’ve been struggling severely for years now. i am both vegetarian and a picky eater, so it’s really hard for me to cut out/reduce gluten, dairy, or carbs—not necessarily because those things are all really good, but because that’s all i can really eat. and for exercising, i cannot do cardio. my body gets winded immediately and i started getting red and sweaty and out of breath so fast that it looks like i just sprinted around the whole block three times. i know it’s kinda a lost cause but like…help!! <3