how to add % to the caption on the side, and create a chart legend icon like below

Hello,

Regarding the questions:

1) how to add % to the caption on the side - This can be done by customizing the ChartValueAxisLabels:

https://www.telerik.com/kendo-react-ui/components/charts/api/ChartValueAxisLabelsProps/#toc-content

2) create a chart legend icon like below - This can be done using a custom visual where you can draw any shape:

https://www.telerik.com/kendo-react-ui/components/charts/api/ChartLegendItemProps/#toc-visual

More details on how to draw shapes can be found here:

https://www.telerik.com/kendo-react-ui/components/drawing/

Regards,
Stefan
Progress Telerik