The unique identifier for the origin request policy that you are deleting. To get the identifier, you can use ListOriginRequestPolicies.
ListOriginRequestPolicies
The version of the origin request policy that you are deleting. The version is the origin request policy's ETag value, which you can get using ListOriginRequestPolicies, GetOriginRequestPolicy, or GetOriginRequestPolicyConfig.
ETag
GetOriginRequestPolicy
GetOriginRequestPolicyConfig