I need opinions about the perspective of my character

[Vicianus]

@SanGent

What I'm going to suggest probably won't be "popular" in your mind, but please consider it. I think you have a good "foundation" in your digital painting right now, the value signatures, shading, and textures are pretty good. You have a cool character.

What really stands out to me is how blatant it is you weren't looking at a pose reference. if you haven't been drawing people with proper proportions, perspective, and anatomy for months and months, trying to pull a pose out of your imagination or memory is a fool's errand. A lot of the issues present in the drawing could have been avoided, quickly, by finding a few solid references of dude's sitting around. For that reason, critiquing or doing a paint over to address things like the perspective or construction seems more like a symptomatic issue of your process than something that will help you to create better drawings over all.

So, let's take a look at possible references. Fortunately, this pose is only a little complicated, but an easy pose to find references for. I googled "Man Sitting" and picked out these three images, which I thought closely resembled or had a "niceness" to them that you could apply to your drawing.

ShutterStock



One of these is even a 3D model, which doesn't matter, because it even helps to distill important information like where descriptive "lines" go in this pose, as well as proportions.

The first thing I notice right away, is that in the pose you've drawn, the man is creating stability while leaning over his legs, by placing his elbows on his thighs. While it looks like the right-side hand might be leaning on the leg, neither arm really gives me the sensation of weight-bearing, and have more of a free-floating look to them.
Some other things I notice in the reference photos are things like how the folds in the shirt create cross-contours that indicate the perspective of the arm. You've rendered your lighting/shapes to be very "flat" and pillowy, like one big rectangle receiving the same light, and unfortunately that does you no good to describe the perspective of the pose. It makes it look like a paper cut-out stacked up.
So, looking at these images, even if I'm not copying them exactly, there's a lot of "language" I can copy to make it seem more authentic, like how to put folds in the sleeves and pant legs to create a sense of overlap and depth.

Obviously though, as far as straight-copying goes, you have to do a bit of mental gymnastics because the poses aren't exactly the same. Your dude is playing with a bunch of cards, so I'll address that next.

Here is a reference photo I found quickly by searching "magician shuffling cards:"


This image is a very close match for the pose of your hands.
The first thing with the hands I'd like to address is that the scale of them in relation to the body is enormous. You mentioned struggling with perspective, so a trick I use to draw proportions in perspective poses from imagination, is to check your proportions against the scale of something closest to it.

For example, in this drawing, his wrist is resting on his thigh, and since we can find out directly the "relative" size of a hand to a thigh (by placing your hand near your thigh and checking the scale, or comparing the sizes of hands in thighs in reference photos) we can determine how big it needs to be, even though our reference isn't exact.

Without talking too much about the "nuances" of anatomy, perspective, or posing, these are the best examples and advice that I can give.

But also, you mentions:

I have a problem with his arms, the right seems not look right. In the shadows i wanted demonstrate Graves in background with a weak silhouette. The perspective is the biggest problem for me.

As far as your lighting goes, this character isn't "really" in the shadows, and he's not really silhoutted. Perhaps thinking about it as a silhouette instead of forms on the character influenced your lighting and made it flatter. If you want to do a painting where things fall out of view in the shadows or blinding light, you have to be a lot more dramatic! Your character is painted entirely in mid-tones, which makes him look to me (or other viewers) like he is fully lit.

So, finally I'll pull out some master examples of lighting where "details" fall into the shadows or are blown out, and the difference in impact:



FRAZETTA GALLERY!!!

These are by comic legend Frank Frazetta. Look at how in the shadows, the details fade out to black and are LITERALLY silhouetted, with very dim details on things like his his belt. On your character, that would be details like his chest straps and those bird skulls.
Legs just falls into the shadows, totally obscured. Likewise, to maximize your lighting impact, your "weakly silhouetted" Graves should fall into the shadows - the tone of the wall behind him, the shadow under his leg, the shadows under the bench. Parts of his body could fade out, and it would make him recede, as though he's a part of that location. In order to do this, you REALLY need o control your tones.

Right now, you're rendering your character in something called "local tones," meaning that you've given him the brown of his hat and hair, straps and boots, the tan of his skin, the blue on his jumpsuit. This kind of coloring gives drawings and paintings a "crayon" type look. You need to shift your thinking to "light" and "shadow" - in studio lighting, and most outdoor-lighting, every object will have a "light side" and a "shadow side." And inside of these areas, there is no overlap in tone. Meaning that in the shadows, there is NO value as light as what appears in the light side.

An example of things that would change if you applies this, is like the bird skulls- His chest is the farthest back, which would be the most "shadowed" and "silhouetted" part in the drawing, yet the bird skulls are bright white. More dramatically, you would probably see the bare outline of their eye and beak in a stark white, with dense and heavy blacks falling over most of the skulls.

This is a good example of the "values" you should see in light and shadow zones, on the classic exercise sphere:



These are all improvements you could make to your drawings right now. Shift your thinking, find good references and examples of what you want to achieve so you can emulate it properly, and keep learning!