If a custom in my country, China, would be introduced to other countries, I would choose lighting fireworks in the Spring Festival as the one.

custom implies doing something, so added the verb "lighting"

First of all, taklighting fireworks has historical and special meaning in China.

Taking sounds like grabbing here. Fireworks is plural, not lighting one single firework in general.

According to the tale, there was once a fierce monster named Nian who lived in the valley outside thea village.

you can use "the" if you can clarify a specific village

Every year, it came to the village and brought disaster.

(now that you introduced the village in the previous sentence, "the" in this case can be used)

For example, it ate people and their goods, as well as destroyed their houses and facilities.

Past tense. You can also break the last part of the sentence and make it its own. "...goods. It also destroyed..."

In order to threaten it and defend themselves, villagers made fires and put bamboos oin it.

preposition

As thea result, the flame and crackling sounds protected them from the monster.

Today, we use firework tos as a substitute the firedfor the exploding bamboo, and the custom has become popular in rural areas when the Spring Festival comenears.

Added a comma because it's a new clause. Fired bamboo seems a bit strange.

Another reason that I'd like to introduce fireworks to foreigners is that it' is interesteding and thrilled playing iting to play with them.

The specific kind of fireworks you might be talking about are firecrackers, so you can replace fireworks with firecrackers if you want. Best to avoid using contractions (it's) if this is an academic piece.

As you can see, playing with fireworks require a little courage and the experience is exciting.

Such a custom will absolutely increase the joy and happiness in the grand festival.

using "the" - which grand festival are you referring to? the Spring Festival or "a" grand festival in general?

For example, when I was a kid, I liked playing with fireworks very much and always wished itfor them as the year came to thean end.

or "looked forward to them." the phrase is usually "came to an end"

When I firedlit the firework, I kept shaking but keput the match steadily to firelight it.

After the powder ignited, I ran away as fast as I can to avoid the bombingexplosion.

"explosion" is usually more associated with fireworks

It was the most pleasurabled and enjoyable time all year aroundof the year for me.

Last but not least, I think the scenes and sounds of firework cracking are splendid.

are is a plural verb

Flying fireworks arsymbolize best wishes from normal familyies for a better tomorrow and thea happier year.

Every people have made therson makes preparations for the fireworks and finally contributes to the scenery.

confused of the use of "finally"

For instance, when the time is 12 o'clock in the Eve ofon New Year's Eve, every family in the community willould launch the fireworks that were prepared about a month ago.

The sky with colorfully lightt sky is a beautiful picture which consistsing of thousands of family's wishes and hopes.

beautiful imagery :'), better flow

In conclusion, I believe that playing with and admiring fireworks areis the fittest custom for Chinese people, and foreigners are welcomed to adopt it and have fun in their own festivals.

one custom therefore "is"

P.S. I think many countries have thea similar custom to what I described but I have to finish the exercise.

ahaha, understood.

Whatever, I choose it as my topic.