What do I tap to go from drawing to eraser

On Apple Pencil (2nd generation), you can double tap to change tools, and what this does for any apps that use Apple’s markup toolbar, can be changed globally in settings (Settings > Apple Pencil if it wasn’t obvious). For apps that use their own drawing toolbars, you can change what this does in their own settings if possible.

On Apple Pencil (1st generation) you’ll need to use the user interface to select the rubber / eraser tool.

Hi Gotoameeting, thank you for posting in Apple Support Communities.

I am not sure which Apple Pencil you have e.g. Apple Pencil or Apple Pencil 2.

Nevertheless most drawing apps on the iPad usually have an Eraser function as part of their Colour Palette. The following link shows the Colour Palette in the Apple Notes app:

https://support.apple.com/en-lamr/HT211774

Furthermore, if you have the Apple Pencil 2, the link also explains how you can setup and use the Double-Tap capability of the Apple Pencil 2 to switch between the Current Tool and Eraser by going to: Settings > Apple Pencil > Double-Tap.