Can you get a touch display attached to a laptop built with a normal display?

As long as your laptop supports an external display, and the display has a connector that matches the laptop's external display connector.

The "touch" functionality is OS/Display driver dependent. You should make sure that:

1. Your OS supports it

2. It has a device driver specifically written for your OS

Yes, but you have to designate the touch display as the primary display and the normal monitor as the secondary.