I really dont know how to look for this so here is a bad drawing of what i mean
Is there a way to make it like in drawing 1? (for unity 3 D).
I believe what you are talking about is called “Oblique perspective”. You can achieve this camera frustrum shape with Physical camera in Unity 2020 (maybe it is implemented in earlier releases as well, but it’s in 2020 for sure). Rotate your camera in Transform component by 90 degrees on X axis. Then, in Camera component tick the “Physical Camera” property, and play with the settings as you wish. Here is a screenshot with the settings that mimic the behaviour you are looking for