IELTS speaking test - Work or study

Hi, I am preparing for my IELTS test. Here is one of my answers speakings. It will be assessed based on fluency and coherence, lexical resource, grammatical range, and accuracy, and pronunciation.

Would you mind helping me to check my writing? Please kindly let me know if there is still room for improvement.
Thank you in advance!

Part 1:
1)Do you work or are you a student?
Before I came to Hainan I was working as an executive assistant for senior management in an international company.
But at this moment, I am preparing for my IETLS because I hope to do a Masters abroad.

2)Why did you choose to do that type of work for?
My career path is from an assistant to operation manager to head of operation department. You can learn a lots from your hiring manager, such as leadership skill, communication skill, presentation skill and so on. Eespecially as if your hiring manage is one of exco members.

3) Do you like your job? Why/why not?
Yes, I love my job because it's interesting and challenging enough. Moreover, I work with a great team from APAC.

4) What is the best thing about your job?
I led 2017-2018 a corporate English training program for over 100,000 associates in China. Before my takeover, this program was only covered 20 associates in Home office.

5) Do you prefer working alone or with others? Why?
I prefer to work as a part of a team. I am a team player with excellent interface [it might be better to use the word communication instead of interface here] skills, but also can work independently to drive for targeted results.

6) Do you miss being student?
Yes. Actually, I am preparing my masters this year, and would like to apply for the 2019 intake of an MBA course.

7) What subjects are you going to study?
I am going to apply for an MBA, specializing in Global business.
Because all businesses in the world now are become globally nowadays. , Iit requires that the leaders to have professional global business knowledge.

【 a Question of Articles in English = 英語の冠詞についての質問 】

Here is one a sentence.
" I went to an art museum in a city yesterday."
「昨日、ある街の美術館に行きました。」

When I Ffirst write this (↑) sentence, if I think of a the Sspecific art museum and the a Sspecific city IN MY MIND in my mind,.
Ccan I first write it Wwith the article "the" instead of the articles "an" and "a" ??...like this,
" I went to the art museum in the city yesterday."...??

※I will appreciate it if you correct my English and answer to my questions.
Thank you in advance! (*^_^*)

My study method

I study English everyday, and have tried various methods.
I'm getting to read, but struggling in speaking and listening.
When I try to speak English, I can't come up with a good expression in English pronounce it well. How do I overcome it this?
Do you know any methods that you could recommend to improve such abilities??

Now I try journaling writing/blogging everyday, it's writting about a small topic whatever is fine. This essay is one of the journaling blogs. I will be able to use some expressions that are used in journaling blogging  in a conversation.

Thank you for reading. Could you correct my sentences? Are there any other ways to say this? If you'd like, please teach me. Thanks.