Lets break down the video and understand what is happening.
- Some level lines are drawn using some formula/logic on the trading view chart (on trading view site and not on zerodha chart)
- The Trading view browser tabs is kept open (so that the market data keeps coming) and when the price touches the lines, a signal is generated, which is then sent to the installed browser plugin(extension).
- The browser plugin (running on users PC browser) using Kite API places the order to users kite account and can cancel and modify it.
All the order firing is happening from clients system, ie the clients system need to be running and be connected to internet and trading view chart must be open in tab. Now here the order gets sent from clients system (clients IP) to the broker and then to the exchange, the regulation aspect and responsibility is now on a user running this software on their system.
Now just for helping you understand more, lets look at the cost aspect, to get realtime data on trading view chart you need to subscribe monthly for $15(approx 1067) + Kite API charges Rs2000, + the browser plugin charges for Rs. 499 = Rs. 3566/month, while you need to keep you PC running and connected to internet.
Hope this clarifies.