a sport competition  - "A sports competition"...when you are entitling the topic, pls start with Capital letters. It should mention as "sports" instead of sport (or) also you can entitle as "Sports Competition"

The World Cup which is hold every four years is my favorite sports event.  "The FIFA World Cup is held every four years, its my favourite sports event"

The 18th World Cup was held in South Africa in 2010. --> This is correct bt still you can make it better.

You shouldnt put so many "in" in the sentence. Instead, you write like this..."2010 world cup was held in SouthAfrica". This looks so simple.

I saw the game everyday even it was at 1 o’clock.--> This is wrong.

"I saw all the matches' (or) games everyday even if it was at 1 o'clock"

Even now I had still remembered the game between Japan and Paraguay. -- Wrong formation because you are using past instead of present tense.

"Even now I still remember the game at johannesburg between japan and Paraguay."

 All the japan players persist in their fight at the last minute.- meaning is wrong

"All the Japanese players persist despite resistance or persists through rains."

Persist - means never giveup.

Rest of your passage, Please try to correct on your own. Finally, this is FYI.

Both " I like to watch" and "like watching" are correct and it often doesn't matter which you use. In British English, there is sometimes a difference between " I like doing " and " I like to do ".

But finally they lost the game. Every player sat on the grass and their eyes turned red. I could never forget that.

I think football is just like a small war, people in the football pitch must use all their wisdom and energy to defend the other side. They must catch every chance and manage to kick a ball around. Even though playing football is a very dangerous game, in the game I found a kind of spirit which always touched me a lot. That is team work.
so anyway, this is why I like watching football game, thank you.