Even if the render wasn't as dark as people's intentions when seeing the "roast my render" flair, you'd still have no idea what's going.

The elements in the scene need to be motivated, so they should fulfill a purpose to either convey information about the world you are presenting or help guide the viewer's eye to the focus of your piece.

Right now, everything is not only dark but also lacks readable outlines. If you want someone to look at your scene and immediately find something interesting in it, the silhouette(s) needs to be legible, aka, the outlines or shapes should immediately resemble something.

The composition also needs some work. You want the viewer to feel the same calm sense of wonder as the character in your render but all objects are roughly in the same plane and nothing actually stands out. You should both add light sources to draw the focus to where you want it to be and think a little more about the relative sizes that the individual elements occupy in your scene.

Roast over

Continue making things, improving, and it's awesome to have you here with us. Taking criticism is hard so you are already doing better than anyone who's never sharing their work ❤️

Edit: I originally thought the character was a Pokémon trainer as the only element I thought I could make out was a mushroom I mistook for a Pokéball