Question

give one example each for Nagara style and Dravidian style of architecture

Answer 1

The Nagara or North Indian Temple Architecture. Nagara is the style of temple architecture which became popular in Northern India. It is common here to build an entire temple on a stone platform with steps leading up to it. Unlike in south India, it doesn't usually have elaborate boundary walls or gateways.
In north India, Brihat-samhita by Varāhamihira is the widely cited ancient Sanskrit manual from 6th century describing the design and construction of Nagara style of Hindu temples. Traditional Dravidian architecture and symbolism are also based on Agamas.