Accidentally deleted my HP Printer and cannot reinstall it.

Download the printer driver compatible with Catalina from HP's tech support website. If your printer is fairly old, they my not have a compatible driver. In that case look for one at Gutenprint Supported Printers.

Hi,

The following article could perhaps be of interest.

Add a printer on Mac - Apple Support

Many printers are AirPrint-enabled, using a driverless technology.

About AirPrint - Apple Support

Drivers/software from the printer manufacturer may or may not add functionality.

If you have further questions, please provide information about the exact HP printer model.