Unity in a program plain, it is necessary to put the camera into the suitable angle only there and already good.
But here,how is needed?
Without complements,plugins,etc...!
I am sure you can not do it here _as_ simply like in Unity.
You have to build up your whole game world in isometric "view".
You can set up the grid system to help you.
Or build up the level from for example xml file and place the obect where they should be in the isometric "view".
https://www.scirra.com/tutorials/1169/b ... projection
http://clintbellanger.net/articles/isometric_math/
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I do not understand.