The best way to transfer your knowledge base to the cloud is to use SaaS software designed for managing and maintaining information. The best tools will facilitate the transfer of your existing knowledge base through a migration tool. That tool should enable you to automatically transfer articles by brand; if you have a small number of articles to move, you can copy and paste as needed.
However, you can also employ partner apps to make the process go smoothly, or you can hire professional help to complete the migration.