consider an alternative to unity or game engines. use opengl.

i made a tree with branches in opengl for example

the leaves are spheres and the branches are cylinders. the trunk is a cylinder too but the radius of it increases when you go downwards

the branches are added randomly recursively and sometimes a sphere of leaves on the end of the branch

i stopped the video game project because i wanted to make own game development tools in this very opengl. but this tool, it would be more about typing commands and instructions rather than hand drawing stuff like in blender.

check the tree below.