Non Stock requisition from Service Logistics

Summary:

We have a scenario that business is creating service work orders, and in order to complete the work need they raise PO or PR for non stock items or services and link it to the service work order,

I have two questions
1- we can use Part order functionality to create PR and PO automatically for Buy items, apart from the Part Request there is no other way to link a PR to a service work order ? Is my understanding correct?

2- if we use the part order functionality how can we raise a requisition and PO for a Non-Stock items?