
Explanation:
Box 1: As a push subscriber and a distributor
To migrate a SQL Server database to Azure SQL Database using replication, you'll need to set up transactional replication with the on-premises SQL Server as the publisher and distributor and the Azure SQL Database as the subscriber. This process involves configuring the replication topology, including the publication, subscription, and the distributor. You'll also need to ensure proper authentication and firewall rules are set up.
Box 2: Transactional with updatable subscriptions
Snapshot and one-way transactional replication are supported. Peer-to-peer transactional replication and merge replication aren't supported.
Reference:
https://learn.microsoft.com/en-us/azure/azure-sql/database/replication-to-sql-database