[Chart/Graph Tool???]

myerf is correct. A very easy work flow looks like this:

1. Put your chart data in an Apple Numbers sheet
2. Create the graph you're needing (note: design your graph as closely to how you want it to look in Affinity Publisher)
3. Select the chart and secondary (right) click on the chart
4. Select "Copy as PDF"
5. Paste in your Affinity Publisher document

This will result in your chart and its associated text and vectors being placed in your AP doc. I have attached two screen shots that show the chart in Numbers and what it looks like when copied as PDF to AP. Each asset and text block is fully editable in AP.