Large volume doesn't always equal lots of price movement, because there could be lots of volume from bears/bulls in a price argument stuck in consolidation... but more often than not the largest volume spikes will happen because the chart is indicating scenarios with high participation.. like a huge dip or a large fomo green candle... Volume can be used as an indicator to buy or sell but needs to be paired with other indicators to whether it means anything or not.
https://www.youtube.com/watch?v=NjxUNcYM-mE - basic volume indicator explanation
Does green-colored volume mean the amount of buying after deducting the amount of selling? And does red-colored volume mean the amount of selling after deducting the amount of buying?