You will need a passport for regional and international travel. Your passport must be valid for at least 6 months after your return and some countries require that you have at least one blank page in your passport. Not complying with these rules will most likely cause the airline to deny you boarding.
As visa regulations differ from country to country, please call the respective embassy directly. Please check with every relevant embassy as per your itinerary about their visa regulations. Please note that certain countries will require a visa even if you are only transferring in that country.