what is the use of form which Candian custom filled at airport during first landing, if we exceds the limit then what is the penalty
You question is not clear.
Canadian Customs don't fill any form for you ( or any person landing)
There is no problem at all if you exceed the limit of declared POF, carried with you while landing.
As per Canadian law, you should declare any amount exceeding $10,000/- for each person while landing.
Question:
What is the benefit of not declaring, if you have excess amount than $10,000/= with you?. Why you should think about a violation of the Canadian law, at the first day of landing itself?. Any how such violation can reach up to a level of confiscation of excess money, if detected or caught by CBSA.