Camunda 8 - Sizing Environment Setup

Hi Team,
I planning to setup the self-managed environement. I am trying to understand the sizing for my environment. When I read below article, I have small query here.
“We typically delete data in Operate after 30 to 90 days, but keep it in Optimize for a longer period of time to allow more analysis. A good rule of thumb is something between 6 and 18 months.”

Where operate data is storing & where optimize data is storing. Is something can be modifiable.
How it is differentiating in elastic search ?

The data is stored in elasticsearch. During the workflow execution, zeebe generates events which are streamed to all its exporters, in this case elasticsearch.

How it is differentiating in elastic search ?

Didn’t follow this question. What do you mean by “differentiating”?

If i understood correctly, Whether it’s operate or optimize it’s differentiated by prefix in ELK.

For example, the property allows to set values for operate:
camunda.operate.elasticsearch.indexPrefix.

Go through the Camunda 8 docs: