[Solved]-ChartJS - How to add Text between Pie Chart and Legend-Chart.js

you can use filter options for customizing your labels

example down below

  legend: {
      display: true,
      labels: {
        usepointstyle: true,
        text: "hello world",
        fontcolor: "black",
        fontsize: 15,
        filter: function(legenditem, data) {
                let labels = data.labels, datasets = data.datasets[0].data;
                for(let i=0;i<labels.length;i++){
                if(labels[i].indexof(legenditem.text)!=-1){
                let t = legenditem.text;
                legenditem.text = t+' : '+datasets[i] + '%';
                break;
                }
            }
            return legenditem;
            },

      },
      position: "bottom"
    }