How to 2.5D ? (with explanatory picture)

Hi! Thanks for response. I also thought about it. Keep the camera parallel to the ground, rotate the sprite to look at the cameraI and put an invisible ground to be able to walk and a “false ground” on the background.
But I can’t because i want to make the player walk up, down, left and right. If I keep the camera parallel to the ground, when the player go to “Z” it doesn’t look in the ortographic camera …