Hello, I would like to ask, in the confidentiality agreement, won't Party B have legal effect different from that that Party B can't have?

"Can't" and "can't" are different in meaning. So the content of the contract is not clear.

Legal provisions: if the agreement is not clear, it can be supplemented by agreement; If a supplementary agreement cannot be reached, it shall be in accordance with the relevant provisions of the contract or

Trading habits are certain.

So in the contract, these two meanings are the same.