However, i do assert an opposite argument that one's success is based on many factors including hardwork,luck,happiness,attitude and certain level of skills.
Avoid more complicated sentence structures. They make the reader tired. You should have nice key words, but sentence should sound easy to comprehend.
However, I do assert that one's success relies on many factors that include both hardwork and luck.Hard work hasplays a significant role in winning life.
... very good sentence :) the word "play" goes better with "role"
For instance,if we work hard,we can learn earn a lot of money or become famous (how can you become famous or well-off? it is not clear)
Ahmad's point is very valid. You need to be more specific about how hardwork would make a person famous or well-off. Give an example; tell about some famous person and how hard he worked towards his goal.
You need to back your reasons with specific examples. It is expected by this task and you would earn marks by doing that :)