Hi
Prudhvi Tavva •,
Welcome to Microsoft Q&A forum and thanks for using Azure Services.
As I understood, you want to know which API of Azure Cosmos DB you should use.
Please check the existing data model you have in DB which you need to migrate. Accordingly the target API could be selected.
Azure Cosmos DB offers multiple database APIs, which include NoSQL, MongoDB, PostgreSQL Cassandra, Gremlin, and Table. By using these APIs, you can model real world data using documents, key-value, graph, and column-family data models. These APIs allow your applications to treat Azure Cosmos DB as if it were various other databases technologies, without the overhead of management, and scaling approaches. Azure Cosmos DB helps you to use the ecosystems, tools, and skills you already have for data modeling and querying with its various APIs.
Refer to this article which can help in choosing the correct API:
https://learn.microsoft.com/en-us/azure/cosmos-db/choose-api
Let us know if further queries. Thanks