Are You Happy?

When I walk along the road, I feel happy. When I ride my bike to roam, I feel happy. When I sit in a cafe, I feel happy. Then I realized, happiness is a simple thing.
However, many people have lost it. They had it.
They are busy with so-called "life." One day, they realized they lost something. At the beginning, they didn't know what they lost. Then they felt sad and hurt. They aren't confident in life.
That's the life. Are you happy? Have you lost your happiness?
Give yourself a vacation. Think about your life.

Don't forget the rules of puncuation spacing and capitalization. Most of the other corrections are for verb conjugation. Those will become more natural with practice.

Original text:

Are you happy

when I walk along the road, I feel happy. When I ride my bike to roam, I feel happy. When I sit in cafe, I feel happy. Then I realize happy is a simple thing.
However, many people lost it.They had it.
They are busy with so-called "life". One day, they realized they lost something.At beginning, they didin't know what they lost. Then they felt sad,hurting.They aren't confident in life.
that's the life.Are you happy? Do you lost your happy.
Give yourself a vacation. Think about your life.

Corrected text:

Are you happy?

When I walk along the road, I feel happy.  When I ride roam about on my bike to roam, I feel happy. When I sit in a cafe, I feel happy. Then I realize that being "happy" is a simple thing. 
However, many people have forgotten how to be happy.  They have lost their way.
They are busy with so-called "life". One day, they realized they lost something. At beginning, they didin't know what they lost.

They are preoccupied and busy completing tasks and fufilling others wishes.  One day, they become aware that they have lost something in their life.  At first, they are not sure what they are lacking ( lacking = missing ).

Then they feel sad and they suffer. felt sad,hurting.They have lost their confidence. aren't confident in life. 
That is (the ???) life.  Do you lost your happy.  Have you lost your happiness?  Are you happy?
Give yourself a vacation. Take a vacation and take some time for yourself.  Think about your life. ( Contemplate life.  What do you enjoy?  What makes you happy )