@Shashank baru Thank you for your patience over the matter!!!
For the mentioned scenario you need to made changed in wp-config file to use azure dB for MySQL server in your Bitnami Wordpress VM as mentioned in below article:
https://wordpress.org/support/article/editing-wp-config-php/#configure-database-settings
Below article might be helpful as well:
https://docs.bitnami.com/azure/apps/wordpress/
Hope it helps!!!
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