How can I make sure that my paper's work is unique?
The only thing you can do to ensure that your contribution is original, i.e., nobody has done the same thing before, is extensive literature research.

Use Google Scholar or Scopus to search for keywords related to your field and try to find something similar. You will notice that there is only so much literature that is closely related to your topic. If you are thorough, you should be able to say if you have done something original.

Your advisor doesn't seem to be keen on talking to you regularly. In the case that you want to continue working for him, you should probably do the literature research, write the article, send it to your advisor for corrections and hand it in. I doubt your advisor will take much time to correct your article, so you should have more experienced colleagues read your article before sending it to him. If he agrees, submit it to a journal and wait for the outcome.