Box 1: Yes -
The createDatabaseIfNotExistsAsync method checks if a database exists, and if it doesn't, create it.
The Database.CreateContainerAsync method creates a container as an asynchronous operation in the Azure Cosmos service.
Box 2: Yes -
The CosmosContainer.CreateItemAsync method creates an item as an asynchronous operation in the Azure Cosmos service.
Box 3: Yes -
Reference:
https://docs.microsoft.com/en-us/dotnet/api/microsoft.azure.cosmos.cosmosclient.createdatabaseifnotexistsasync
https://docs.microsoft.com/en-us/dotnet/api/microsoft.azure.cosmos.database.createcontainerasync
https://docs.microsoft.com/en-us/dotnet/api/azure.cosmos.cosmoscontainer.createitemasync
