Hi Jinse T J
Yes, if you upgrade your subscription to Pay-As-You-Go or another paid plan, you will typically gain access to additional regions, including South India.
The South India region is fully supported in Azure and is listed in the official Azure regions list, paired with Central India. Free Trial accounts may not show certain regions or VM sizes due to region restrictions or capacity constraints.
Reference: https://free.blessedness.top/en-us/azure/reliability/regions-list
Upgrading: https://free.blessedness.top/en-us/azure/cost-management-billing/manage/upgrade-azure-subscription