Hello,

If you want to be a fashion designer then go for it. If you don't like your study or career path then it's really stupid thing to do forcefully any work. Just prepare yourself for fashion designing examination. 1 to 2 months is not for enough but for qualifying it's enough. I hope you can get any good college.  And you can said to your parents ofcourse that you want to be a fashion designer.

All the best.