It shows CPR range as per yesterday's HLC and also CPR range for last n number of trading sessions.
For example: If you mention the value as two in Multi-day CPR (blue color) then it calculates the CPR using HLC of the last two trading sessions.
Also, the daily CPR is designed in such a way to highlight Virgin CPR (purple color) separately from the normal CPR(fuchsia color).
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.