Is it necessary to create a request to create an Estimate in Zoho FSM? Can I create an Estimate directly without creating a request in Zoho FSM?

Is it necessary to create a request to create an Estimate in Zoho FSM? Can I create an Estimate directly without creating a request in Zoho FSM?

No. It is not necessary to create an request to create an estimate.
You can create an estimate directly without a request.
Refer help doc for how to create a new estimate.