Hi @mbhammad,
You could refer to the following steps to create the work item of DevOps according to the created or modified items in the SharePoint, then add the attachments into it.
This is the whole steps:
These are key steps that you need to notice is send the HTTP request to create the Attachment.
- Upload Attachment
Full documentation for this endpoint can be found here: https://docs.microsoft.com/en-us/rest/api/azure/devops/wit/attachments/create?view=azure-devops-rest...

- Parse JSON
{
"type": "object",
"properties": {
"id": {
"type": "string"
},
"url": {
"type": "string"
}
}
}
- Relate Attachment
Full documentation for this call can be found here:
https://docs.microsoft.com/en-us/rest/api/azure/devops/wit/work%20items/update?view=azure-devops-rest-5.0

This is a simplified step, a lot of details have been omitted, the specific source is from @MattWeston365, if you want to know more, you can click on this blog:
https://blog.mattweston365.com/2019/06/uploading-attachments-from-sharepoint.html
Best Regards,
Community Support Team _ Lin Tu
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