A job interview is like an exam, where they try to cut you off by asking the most unexpected questions. Even a decent candidate with a good resume finds it difficult to break through this barrier. I advise you to read as much as you can about interview questions and situations at employability20.it.
It's also a good idea to first understand the field of work, read an article about the dress code and choose a style of dress that will help the employer immediately understand that you are on the same wavelength as them.