Hi Shreya,
You can use a button to call a microflow, and pass the uploaded file to that microflow inside you can call post service and pass the file based on the api.
Thanks
lets say, your api has this signature: sendFileToApi(file: FileDocument)
In the sendFileToApi microflow, use the HttpRequest and HttpResponse modules to send the file to the API. –
You can use the HttpRequest.setBodyContentFromBinary method to set the body of the request to the contents of the file, and then use the HttpRequest.send method to send the request to the API.
Handle the response from the API in the sendFileToApi microflow, and use the Commit action to save any changes to the database if necessary.