Hi @Baljit Singh (HCL TECHNOLOGIES CORPORATE SER) Welcome to Microsoft Q&A thanks for posting your question.
You can use the Azure Private Link feature to connect the two databases securely and privately.
follow the document here for more information https://learn.microsoft.com/en-us/azure/azure-sql/database/private-endpoint-overview?view=azuresql
Also, here I found a similar ask on SO forum https://stackoverflow.com/questions/74821726/how-to-connect-to-azure-sql-database-without-ip-whitelisting
Regards
Geetha