The Live Charts allow you to create a chart, but it doesn't support the specialized burndown chart. The closest you can get is by specifying an X-Axis value of "Enter Work Date" (or whatever event you're using to record hours worked). This would show the reduction in work over time, but the X-axis would only show days that the remaining work changed rather than a consistent timeline. It also is missing other burndown chart elements like the projected end.
Burndown charts are a special type of chart that are only available from a burndown report or a burndown dashboard widget. The following two links have information about these two burndown options. You might consider using a burndown widget on a dashboard to display your project's status, rather than a live chart.
https://help.perforce.com/alm/helixalm/2019.2.0/client/Content/Admin/AddingDashboardBurnDownWidgets.htm
https://help.perforce.com/alm/helixalm/2019.2.0/client/Content/ClientUser/ReleaseStatusReports.htm?Highlight=burn%20down%20report
Regarding the icons question, I'm not sure which icons you are referring to. Maybe you're talking about the Field Value Styles, which can be configured by the administrator?
https://help.perforce.com/alm/helixalm/2019.2.0/client/Content/Admin/AddingFieldValueStyles.htm?Highlight=field%20value%20styles
