Hi @Koteswararao Kata ,
Thanks for the elaboration. I read through your description but based on my knowledge and research, I am afraid neither of the two requirements can be realized.
For Requirement 1, as we can learn from this article, DLP Policy templates are expressed as XML documents which adhere to certain schema. With the built-in features and cmdlet available, we can only export the DLP policy collections using the Export-DlpPolicyCollection cmdlet, but its output is far from adequate to develop a Policy template. Given this, you would need to refer to the first link mentioned earlier to manually developing the DLP policy template files based on your need.
For Requirement 2, per my understanding, the DLP policy is independent from the policy template after it's been created, therefore I'm afraid it's not feasible to make changes applied automatically to the "child policies" when a change is made in the "main policy".
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