Then it's the percentage price change between the open and close price of a single candle on a given time frame. If it's a 5-minute chart, then that small percentage change represents the price change of Bitcoin in those 5 minutes, represented by one candlestick.
That's what I thought at first but it turned out to be that it's not. Changing the time frame does not change the percentage.
2. I did some small research and apparently trading view shows the 24 hours change
Change of what? The percentage? If so then what's the difference between this and the above time frame change?