This is Cumulative Delta Volume script. Delta refers to the difference between buying and selling at each price level. Cumulative Delta builds upon this concept by recording a cumulative tally of these differences in buying vs selling . The Cumulative Delta indicator plots as or line. One of the main uses of Cumulative Delta is to confirm or deny market trends. you may need to search it for yourself ;)
You have option to see it as Candles or a Line. also there are options to show 2 SMAs and 2 EMAs with different Lengths, you can set the lengths as you wish.
By default it shows CDV as Heikin Ashi Candles, it can also show it as normal candles:
It can show CDV as a line:
Also you may need to check divergence: