Im really new to blender and this is the extent of what I know how to do somewhat well. I want to push this through and see if I can get photorealism. Id likes to add some volumetric shadows and lighting.
Are you using an HDRI?
Are you using reference photo(s)?
First, although you’re chasing photorealism in your scene, adding in the volumetrics fog it seems you captured an “interesting quality, a detailed Toonish “Wind in the Willows” look which is cool.
Regarding photo realism - look to your render settings, I’d “Up the render per cent age” to like 150%. Cause although others will likely push for Field of View blurring of the edges, your key subject elements in the center will benefit by the extra detailing.
Also, it appears you’re using Grasswald. Some transparency of the leaves to light is key to gaining a realistist sense. Which requires some element of rim Lighting “behind the scene” shining towards the camera to illuminate leaf edges and the leaf itself.
Hopfully, this is accurate and helpful.
"Clua 'ya, there ain’t no such thing as ‘photorealism.’" Every professional photograph is a compromise of conflicting concerns – just like CG – and is actually “very contrived [also].”
First question: “What do you, the ‘photographer,’ want from your photograph?” What’s the subject? The can? Is there a snapping-turtle back there? The grass? Your composition must “at a glance” lead the viewer’s eye through a carefully-intentioned pathway which starts at “the brightest and most-contrasty part of the image” and leads by a closed circular path back to the starting point – thereby introducing the viewer to exactly the image-elements that you, the visual storyteller, want him/her to appreciate.
(Sounds hard? It is. Imagine doing it with film!)