To start your career in ethical hacking, first, collect all information related to it, like everything about hacking, what subparts n topics in it, What kind of job opportunities this field offers. You can easily find your answers on the internet. Go through various articles, blogs, videos. After that, you will get a clear idea of what hacking is.
Then you can go for the ethical hacking course, there are a lot of institutes that provides this course, but before choosing any institute make sure it offers, course syllabus you are looking for, and training is done by industry experts.