I'm thinking of canceling a job interview because they asked me to wear a suit
Why don't you want to wear a suit for your job interview?
I don't like business suit I just wear it because they tell me to do so.
In most cases, when you attend an interview, you want to make sure that your attire aligns with what people typically wear in that workplace. If you are looking for a position in a profession where wearing more formal clothing is the norm, then putting on a suit might be a necessity if you want the job and make a good impression.
I don't care what they think. I want to wear something different at the interview.
Then don't expect to get the job, then. Wearing proper attire in an interview is part of the process of getting hired. You wanting to skip that shows that you aren't serious about landing this job.