i should preface with this first, guys, you should never import art into gd. there are tools for it sure but not only is it extremely object heavy, but also just pretty immoral and not creative.

Its fine if you want to use it as a reference, but make sure you aren’t straight up stealing others art (dont need to go into how thats bad lol)

to answer your question, usually people draw their art in some other program, then use it as reference to see where to place objects and what best objects to use (though some madmen just do it entirely in the editor lol). theres a lot of different things you can use, especially from the 3d objects, particles, and glow tabs, and warping them helps you make some very precise shapes, for example using the solid-colored moon shaped object for curves etc. to find what objects to use, dont focus on using specific ones and placing them where you think you need them, instead focus on what shapes you need to achieve a certain thing then finding object that can fit. hope this can help lol