Hi Hannah! That's great that you know so many languages! Good luck studying English!

Here are some corrections for you:

Nice to meet you.

Hello, I'm Hannah from Taiwan. I speak Chinese and Taiwanese. I can also speak Korean.
I want to improve my English skills.Because because I want to treval for travel to other countries.
If you want to learn Chinese, I can help you. But I don't know Hanyu Pinyin, I only know Bopomofo.

안녕 하세요.저는 양함입니다.지금 타이페이에 살고 있습니다.

***Note: I added a space between each period ( . ) and the beginning of the new sentence... Make sure to always add this space in your writing. Also make sure to add a space after a comma ( , ). Thanks!***

Nice to meet you.

Hello, I'm Hannah from Taiwan. I speak Chinese and Taiwanese. I can also speak Korean.
I want to improve my English skills because I want to travel to other countries. 
I can help you if you want to learn Chinese, but I don't know Hanyu Pinyin. I only know Bopomofo.

안녕 하세요.저는 양함입니다.지금 타이페이에 살고 있습니다.