So, I will be working in Taiwan for 5 months starting in October. I have never even left the United States so bear with me. I'm a 23 y/o M. While I will be working in Taiwan, I will make sure take some time off to travel to other countries. I'm thinking I will have 3-4 opportunities (roughly 5 days long each) that I will be able to fly wherever I want. So, can anyone give me recommendations of what are must-see things while in Asia?

I am interested in a little bit of everything when it comes to traveling. I love nightlife, cities, beaches, and backpacking trails/exploring national parks. I'm truly open to any suggestions, so please let me know what you think are the places that I should not miss while I will be living in Asia!

Lastly, since I won't be able to travel too many days at a time, the closer to Taiwan the better (Japan, China, Thailand, Singapore, etc.)