who is your country's most famous celebrity ??

who is your country's most famous celebrity ??

I think the most famous person in my country is PSY. (Perfect)
He is a singer and he makes the songs himself.
His song, that named Gang nam Style, is popular around the world.
First, His music video made him famous around the world.
His dance is also very famous. Many people like to dancing by to his song.
It is very a lot of fun. and I'm very proud of him.

If you use 'First, ....' you need to follow with 'second, '' otherwise there is no point in using 'first, ... ' You could say:  First, his dance moves was goofy and second, his music was very catchy. This is what made him popular around the world.

What I believe you are trying to say is the following:

I think the most famous person in my country is PSY. He is a singer and he writes his own songs. His song, Gangnam Style, is popular around the world and it was the music video which made him famous. His dance is also very famous. Many people like doing his dance moves in the video. It is a lot of fun and I am very proud of him.

PSY is great. I laughed so hard when I first saw that video. I had no idea what he was saying but the video was brilliant, artistic, and unique. I believe that is what caught the attention of most people outside of Korea. The music was also catchy, so I believe that had a factor as well. I visited Gangnam a year ago so I know what it is like there. I had to get my friends from Korea to help me understand what he was saying. I am happy to see Korean music growing to the level it has in the world. Korea is the first Asian country to have a 'big hit' spread in the western world. I knew it was going to happen someday. And it wasn't even in English! Amazing!