I checked out a funny vedio clipideo from a variety show.

Video clip is okay, but just video works too.

One of the guest is was DaBing, who is a talented impersonator.

He iwas also quick-mindwitted and humorous whefunny in heis retortedply to the host‘s joke.

If there's multiple instances, "replies to the host's jokes"

I nearly died laughing in five minutes and had a boundless feeling.

Do you mean:
1. the clip was five minutes long, and you laughed through the whole thing?
2. the clip was five minutes long, and (despite the short length) that was enough to get you laughing really hard, but you didn't necessarily laugh through the whole thing?
3. the clip was longer, but five minutes was enough to send you?

Some suggestions for each
1. I laughed so hard through the whole five minutes I nearly died, and I felt weightless.
2. The five minute clip had me laughing so hard I nearly died, and I felt weightless.
3. Within five minutes, it had me laughing so hard I almost died, and it made me feel weightless.

SuddenlyBut then, I saw some comments saying he had passed away because of drugsof drug overdose.

"Suddenly" doesn't really work here for some reason. You don't really see the comments "suddenly". I guess if the comments were there on the screen (meaning you didn't have to scroll to them), you could say that "suddenly" the comments caught your eye.

I amwas shocked!

I guess "I am shocked" kind of works, I assume you are still shocked by it during the time you're writing this. But I think "I was shocked" is better. It kind of emphasizes that initial reaction.

Then I read an article about how he had been struggleding with addiction.

I think the continuous aspect helps emphasize the prolonged struggle.

In a span of five years, he washad been caught four times and sent to detoxrehab three times.

It's a little unclear what you mean by "caught". Caught doing drugs? Caught being on drugs? Caught having drugs? I guess it's not that important.

If it's the last five years of his life, you can say "In the five years leading up to his death"

Random note on rehab/detox: rehab is a noun, and "detox" sounds like a verb in your sentence.

Every time, he swore that he would never touch drugs, but he cannoouldn't keep his promise.

He destroyed his carediter and career pathreputation.

I felt so sad because he made things as jolly for the audients but he was caught by theaudiences happy, but he was plagued by sadness and physical pain.

Instead of "sadness and physical pain", since you're bringing up physical pain, maybe "physical and emotional pain"?

I hope nobody would beill get ruined by drugs anymoreever again, though I knew it is a miragerealize it's hopeless.

I checked out a funny vediideo clip from a variety show.

He is also quick-minded and humorous when he retorteds the host‘s joke.

Every time, he swore that he would never touch drugs, but he canould not keep his promise.

I felt so sad because he made things as jolly for the audientsce, but he was caughttrapped by the sadness and physical pain.

I think you meant trapped when you said "caught" because of the way the sentence was worded, but caught could also work in some scenarios.

I hope nobody wouldill be ruined by drugs anymore, though I knew it is a mirage.

I checked out a funny vediideo clip from a variety show.

He iwas also quick-mindwitted and humorous when he retortcountered the host‘s jokes.

I nearly died laughing in five minutesWithin five minutes, I was dying of laughter and had a boundless feeling.

One would not say in English that one "has a boundless feeling," as it makes no sense in English. You could say that you laughed so hard you felt weightless, but I'm not sure how to change it for you and preserve your meaning perfectly.

Suddenly, I saw some comments saying he had passed away because of a drugs overdose.

Drugs themselves don't usually kill people, but one would refer to an overdose in English.

I amwas shocked!

Every time, he swore that he would never again touch drugs, but he cannoouldn't keep his promise.

He destroyed his creditputation and his career path.

I felt so sad because he made things as jollyfun for thehis audientsce but he was caughtovercome by the sadness and physical pain.

I hope nobody would beis ever again ruined by drugs anymore, though I kneow it is a miragethat hope is wishful thinking.

A mirage is used in English to talk about an illusion in the distance, though it is definitely not the right word here to talk about one's hopes for social causes because you're not personally working towards it. If it were some kind of goal in your life that you hope after, you could talk about that hope being a mirage, but not if its a vague hope that something will change in the future without your input. I substituted it for 'wishful thinking' since 'mirage' didn't fit here.