I'm a passionnate person, so I have a lot of diverse passion.

PASSIONS plural

But my biggest passion is to listen TO people speak about themSELVES.

"to listen to" or "listening to"

I think each person is like a book and I could pass an entire day to listenLISTENING TO someone speak about what he did onIN his life, what he loveS, his dreamS, his regrets, his failures...

"on his life" is grammatically incorrect. We do things IN our lives.

I love old people, [no comma needed] because they have a big story behind them, and they often like to speak about their memories.

It's the reason I [very] want to improve my eEnglish, because I want to speak with more people around the world.

It is grammatically incorrect to say "I very want."
The names of languages are CAPITALIZED in English.
It is not necessary to use both "the reason" and "because." The sentence is long and repetitive with both.

I would like to share the story of everybody onIN the world.

"on the world" is grammatically incorrect.

I think we can learn a lot ofrom others.

"of others" is grammatically incorrect.

So, if I need to resummarize:

The verb "resume" means to start again. The verb "summarize" means to say restate everything, or your main points, in a short statement.

I'm passionnate byABOUT people.

"by people" is grammatically incorrect here.

My Greatest Passion.

I'm a passionnate person, so I have a lot of diversefferent passions.

I love to draw, read, write, sculpt, walk.., etc.

ButHowever, my biggest passion is to listening to people speak about themselves.

It is best to not start a sentence with 'but'!

I think each person is like a book and I could pass an entire day to listening to someone speak about what he did ohas done in his life, what he loves, his dreams, his regrets, his failures.. etc.

I love old people, because they have a big storyies behind them, and they often like to speak about their memories.

It's the reason I verreally want to improve my eEnglish, because I want to speak with more people around the world.

I would like to share the story ofstories with everybody oin the world.

I think we can learn a lot of from one anothers.

So, if I need to resumto conclude:

I'm passionnate byabout people.