First statement is incorrect because though the traces of Pallava and Chalukya temple architecture are available, but its construction is generally attributed to the 8th century Rashtrakuta dynasty. The second statement is also incorrect because the temple is a complete dravida building
Greeks, Kushanas & Shakas had entered India through the North West side. Accepting the local religion would provide them the easiest way to achieve legitimacy of their rule. Since Buddhism was prevalent in the area at that time and it was provided easiest entry (Hinduism had st5rict caste based structure) so, they embraces Buddhism.
In the Battle of Vatapi, the Pallava ruler Narsimhavarman I defeated and killed Pulakesin II and captured the Chalukyan capital, Badami in 642 AD. Thus, he assumed the title of ‘Vatapikonda’ (Conqueror of Vatapi).