Tick "Enable Auto Workflow" to create the auto workflow for purchase order/ request for quotation. You can choose the default workflow from here or you can choose workflow from request for quotation/purchase order.

Now go to the "Configuration" => "Auto Purchase Workflow".

Auto purchase workflow form view looks like this. We provide below options for auto workflow, Auto-validate order, Auto-create bill, Auto-validate bill, Default purchase journal, Auto-register payment, Default payment journal, Default payment method.

You can choose created workflow in the default workflow from here.

You can also choose workflow from request for quotation/purchase order.
When you create a request for quotation if you select auto workflow then press the "Confirm" button to proceed with workflow as per the configuration.

Based on workflow configuration all operations performed quickly.

As you can see, the 'Receipt' is processed automatically in done stage.

As you can see, the bill is automatically paid.