Beginner Game dev question

Good day everyone, im making a 3 game which is a virtual tour of my school and i would like it to allow players to sit at a computer and play a 2d game in the game. So in better terms within my 3d game open a 2d game

What is the question?

i apologise i want to know how would i open a 2d game in a 3d game?

You want the 2D to be a different executable?

Otherwise, you can have a scene with the 3d stuff, a scene with the 2d stuff, load both, render the 2d stuff to a texture, put that texture in the monitor.