There's a Chinese restaurant justnear me which had opened six months ago in my town.

We use "had" because, it is a situation that has already occurred in the past.

However, I'm curious that how long the restaurant would lasts.

Same here, it's in the past.

For some reason, if a restaurant opens at theat place, every time itot, it would closes within a year.

Before the Chinese restaurant, there was a ramen shop, but it closed too soon, so I didn't get to go.

There's a Chinese restaurant that just opened six months ago in my town.

I went there two times.

What you wrote is correct, but another way to say this is, "I've been there two times."

However, I'm curious that how long the restaurant will lasts.

For some reason, ifevery time a restaurant opens at theis place, every time it closes within a year.

Before the Chinese restaurant, there was a ramen shop, but it closed soon, so I didn't get to go to it.

If the Chinese restaurant closeds, I would'll write about it here again.

There's a Chinese restaurant in my town that just opened six months ago in my town.

However, I'm curious that how long the restaurant will lasts.

For some reason, if a restaurant opens atin the place, every time itat location, it always closes within a year.

Before the Chinese restaurant, there was a ramen shop, but it closed soon, so I didn't get to go.

My friend told me that ithe place might be cursed.

We already know you are talking about this location by now, so you can use a pronoun (it) instead of saying "this place"

If the Chinese restaurant closeds, I wouldill write about it here again.

There's a Chinese restaurant that just opened six months ago in my town.

I went there two times.

You can also say "I went there twice."

However, I'm curious that how long theat restaurant will lasts.

For some reason, ifwhenever a restaurant opens at theis place, every time itit always closes within a year.

If you still want to use "every time" like that, you should move it to the end of the sentence like this: "it closes within a year, every time." Otherwise it sounds like you are about to mention something that happens each time the restaurant closes (example: "every time a restaurant closes, a new one takes its place.")

Before the Chinese restaurant, there was a ramen shop, but it closed soon, soon that I didn't get to go.

There's a Chinese restaurant that just opened six months ago in my town.

I whave beent there two times.

You can also say “twice“ instead of two times here to sound more natural.

The food was good, and I liked it.

However, I'm curious that how long the restaurant will lasts.

For some reason, if a restaurant opens at theis place, every time it closes within a year every time.

Before the Chinese restaurant, there was a ramen shop, but i. It closed soon, soon that I didn't get to go.

There's aMORE SUCCINCTLY: A Chinese restaurant in my town just opened six months ago in my town.

You came delete "There is . . . "

I wALSO POSSIBLE: I have beent there twice/two times.

Usually we say "twice."

However, I'm curious that how long theat restaurant will lasts.

(future tense needed)

For some reason, if a restaurant opens at the place, every time it closeCLEARER: Most restaurants in this area go out of business within a yeabetter.

Before theis Chinese restaurant, there was opened, a ramen shop, but existed there. However, it closed soon, so I didn't get to goo there.

If the Chinese restaurant closeds, I wouldill write about it here again.

There' is a Chinese restaurant that just opened six months ago in my town.

I went there two times.

However, I'm curious thaabout how long the restaurant lasts.

For some reason, if a restaurant opens at the place, every time it closes within a year.

Before the Chinese restaurant, there was a ramen shop, but it closed soon, so I didn't get to go.

If the Chinese restaurant closed, I would write about it here again.

There's aA Chinese restaurant just opened six months ago in my town.

This sounds more natural.

I went there two times.

Alternatives:
I went there twice. / I have been there twice.

However, I'm curious thato know how long the restaurant will lasts.

For some reason, ifevery time a restaurant opens at theat place, every time it closes within a year.

Before the Chinese restaurant, there was a ramen shop, but it closed soonquickly, so I didn't get to go.

If the Chinese restaurant closeds, I would write about it here again.