[Solved]-How to make stacked column graph to show total data value on top-Highcharts

Here is how:

yAxis: {
            allowDecimals: false,
            min: 0,
            title: {
                text: 'Number of fruits'
            },
            stackLabels: {
                enabled: true,
                style: {
                    fontWeight: 'bold',
                    color:'gray'
                }
            }

        },

You have to use stackLabels. You missed it in your code. You can find it in yAxis -> stackLabels

 stackLabels: {
    enabled: true,
    style: {
        fontWeight: 'bold',
        color:'gray'
    }
 }