Hello @pratap_penmetsa,
Please below REST endpoint URL to generate invoice
Endpoint URL: http://magento.com/index.php/rest/V1/order/{order_id}/invoice
Request: POST
Header: Authorization bearer {access-token}}
I have also tried above Rest API, You can check result here https://www.screencast.com/t/xOCyjalmT
After get invoice id, you can get invoice data by http://magento.com/index.php/rest/V1/invoices/{id} rest api, You can check more detail in my previous comment.
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If my answer is useful, please Accept as Solution & give Kudos