Please put a blank line between paragraphs.
Like this. Indenting the first line of the second and following paragraphs is an acceptable alternate. If you do neither, it's hard to read your text.
> cot to sleep.
- cot to sleep on.
Compare "book to read" and "things to do." "Cot to sleep" makes "sleep" sound like a transitive verb.
> that he works
- that he worked
> but he could just earn
- and could only earn enough money
Optionally, "the boss." But it's okay to turn a common noun into a proper noun when you're telling a story, especially if you want it to sound like a folk tale.
> asked Tom if he could work an extra hour, he could increase his salary to double.
- asked Tom if he could work an extra hour and offered to pay him double wages.
The parallel is "Boss asked ... [Boss] could increase" - I changed it to use the same form both times. This improves readability.
> one of his friend
- one of his friends
I'd spell it out, especially because the narrator is speaking.
> could not think to invite his friends
- could not imagine inviting his friends
"Think to do" : realize something needs to be done and do it
"imagine doing" : think about doing something
> he can double
> one of tomís friend
Same as above.
I do not know why this is capitalized.
> to the work place
> things he ever liked
- things he had wanted
- In fact
I'm going to point out the remainder of the errors or rough spots without correction.
> so used to wake up
> he was sleep less
> into an emergency where doctor told him
> so he developed insomnia and so other diseases
> a a grand and beautiful cot
cot vs bed
> does not have the sleep in his eyes
I like this idiom, but it isn't standard.
> he had food but he could not eat food
> we cannot our body back now..
> he was so revealed
> that he is out of all the diseases
- that he didn't have any of the diseases
> is ... are
> that he always wears one pant
- because he always wore the same pair of pants
"Pants" is always plural. You need "pair of pants" to count them. Weird, but that's the way it is.
> determined not to bother by his friend
- determined to not be bothered by his friends
The story is functional, but low-intensity.
- Give Tom somebody or something to care for, a family or a pet or goals. He doesn't just sacrifice his health along the way, but his obligations to others.
- Expand the description of physical places. This is fine as a flash story, but it could also be the outline for a novella.
- Either remove the "it was all a dream" part at the end, or show Tom's classmates taunting him. Putting that detail at the end puts it out of order.
I liked it, especially since I know how hard it is to tell a story even in my native language.