I wouldn't say a virtual keyboard is a good idea because of the lack of tactility. We can discuss in tomorrow's meeting but here's a summary of considerations for the keyboard I've found:
Considerations for the keyboard
Many braille display devices have Perkins braille keyboard – for this device we want to use familiar qwerty.
Find a suitable Keyboard to fit our frame and look for Braille/ Contracted Brail Keycaps for the Keyboard.
Alternative:
Try to use the Raspi5 touch screen to have a virtual keyboard to learn kids to touch type wit h ????