Hi Md Shervin •,
Welcome to Microsoft Q&A forum.
As I understand, you want to know ways to perform Backup and Restore in Azure Database for PostgreSQL Flexible Server.
By default, Azure Database for PostgreSQL flexible server enables automated backups of your entire server (encompassing all databases created) with a default retention period of 7 days. The automated backups include a daily incremental snapshot of the database. The log (WAL) files are archived to Azure Blob Storage continuously.
You can manually take a backup by using the PostgreSQL tool pg_dump. For examples, see Migrate your Azure Database for PostgreSQL flexible server database by using dump and restore.
If you want to back up Azure Database for PostgreSQL flexible server to Blob Storage, see Back up Azure Database for PostgreSQL to Blob Storage on our tech community blog. Restoring a single database or a few databases or tables is not directly supported. However, you can restore the entire server to a new server, and then extract tables or databases and import them to the new server.
For more details refer to https://learn.microsoft.com/en-us/azure/postgresql/flexible-server/concepts-backup-restore
Let us know if this helped or you have more queries.
Thanks