Hi Rohith,
Thank you for reaching out to AdWords API and Google Ads API Forum.
For cURL requests in AdWords API, you should read and refer to the documentation here: https://developers.google.com/adwords/api/docs/guides/call-structure#request
In the guide, point 3 describes adding a budget in hello_world.xml:
Create a SOAP request. The following sample XML snippet defines a SOAP request that adds a budget. Save this XML (with your authentication token and account login replacing the placeholders) as hello_world.xml.
You should replace this XML file with your use-case of pulling reports. Please read up on the Reporting guides available here: https://developers.google.com/adwords/api/docs/guides/reporting
Hope that this helps
curl --header "Content-Type: application/soap+xml" \
--header "Authorization : Bearer access-token" \
--data @<report_definition>.xml \
https://adwords.google.com/api/adwords/reportdownload/v201809