API Permission from Broker Houses.

I have a ready coded Algo-trading program but my broker house is not ready to share its API for me to utilise the services of Algo-trading on its trading platform. What should I do? If I approach the share market data providers and utilise their data, is it possible for me to trade using Algo-trading directly in the exchanges? If yes, how about the generation of various governmental taxes?

The Algo-trading code may be developed on AFL or Tradingview.

Zerodha, Aliceblue provide API service