Here is a link to my work, (its crap I know)
https://inkbunny.net/submissionview.php?id=610401

To create this I first used a pencil and paper to sketch out a pretty good outline, then I transferred it into SAI for line work then coloring and shadowing. One question I have is how to add more detail, my work looks very simple with such little detail. I can shadow but that's about it, how do I go about shading to add complexion and adding light spots?

When I look at the work of the pro's, with all their detail, it frightens me, but I realize it will take years for me to get to a decent level. My goal is that at the end of summer I should be able to produce work that is qualified to be posted on this site, something maybe akin to Luka or ChanceBandit.

Honestly, your work is better then what I have seen.

Just keep practicing, maybe look into doing art classes and I'm sure I'll be approving your art on e621 in no time.

Don't give up.

for the future keep in mind proportions of things like body parts, do not make someones arms thicker than there legs for example, so make sure that things like penises don't look absurdly big or absurdly teny for charecter of requests physical build you don't have this issue now but i'm just saying this to keep you on your toes!

Here's my advice:

1. Practice drawing circles until you can almost draw a perfect circle, so that you can get a feel of drawing curves and it helps keep your hand steady.

2. Take your time. No one is rushing you, it's just you and the tablet or paper.

3. Patience. Art is a process, it will get better but you have to be patient.

Your lines are a bit wonky, but since you're using SAI you can work around this with the stabilizer.

You'll get smoother lines this way.

Other than that look up tutorials on Youtube, watch streams etc.
For example this guy has some pretty good ones.

I'd say you ought to practice sketching out a basic stickman skeleton for your characters before you start in on detailing them. This is basically just circles and sticks that show where the parts of the body go in relation to each other. Most How-To-Draw books should start out with a section on this.

Practice drawing circles until you can almost draw a perfect circle, so that you can get a feel of drawing curves and it helps keep your hand steady.

This is very helpful :)

practice anatomy. practice a lot of anatomy.

He looks hungry. Just remember when it comes to muscles and abs, the abdominal muscles aren't all that far above the hips, when they get too high, they start to look like ribs, making your character look anorexic.