REFUND ON EXPORT OF GOODS TO NEPAL

Yes I think you need to file RFD_01 for claiming refund.

No not required to file RFD 01.

Export of goods to Nepal fulfils the condition of GST Law regarding taking goods out of India.  Hence, export of goods to Nepal will be treated as zero rated and consequently will also qualify for all the benefits available to zero rated supplies under the GST

The shipping bill filed with the Customs is treated as an application for refund of IGST and shall be deemed to have been filed by furnishing of a valid return in Form GSTR-1 & GSTR 3B by the applicant.

so once you have furnished the export details in GSTR 1 & GSTR 3B it's deemed that application for refund being filed .

Note : When goods is exported through Land Custom , Bill of Export is filed at India Border .