Thank you for your question.
I’d recommend having a look at our page on reporting on https://octopus.com/docs/administration/reporting
This discusses the ways the raw data about deployments is made available for uses such as reporting.
If the raw feed doesn’t provide all of the information that you are looking for, then I’d also suggest taking a look at the API that is available in Octopus. You can find out more about this on https://octopus.com/docs/octopus-rest-api.
We also have a collection of API scripts that you might find useful when building a script to query the API. You can find these available on Github on https://github.com/OctopusDeploy/OctopusDeploy-Api