Orthanc server on live server

Can we use Orthanc server on live server like Digital Ocean or it just for localhost and can be used within an Intranet? Any advice and suggestions will be greatly appreciated.

You may use it in the cloud. However, you should be aware of some limitations regarding security of data:

To implement more complex access level management, you should consider writing a webapp to handle users (and eventually other business logic). In that architecture, Orthanc would just be an image DB.

Any suggestion for which cloud to use and how to use it with orthanc.

Nutanix has published such a tutorial:
http://myvirtualcloud.net/how-to-deploy-open-source-pacs-on-nutanix-acropolis-container-services-with-persistent-storage/

But Orthanc is now to work on any cloud infrastructure that can deploy a Linux virtual machine.

Thank you for your prompt reply.