When you have me you feel like sharing me but if you do share me you don’t have me what am I

A secret. When you have a secret, you want to tell other people, but when you do, it's no longer a secret.

A secret

Explanation:

When you have a secret, you want to tell other people, but when you do, it's no longer a secret. Hope this helped :)

cell is a basical, structural and functional unit of life

An atom is a particle of matter that uniquely defines achemical element.

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