It's ya boi

Hello from ProjectComment!

First off - what a cool design! Nice colours that work together well, and a unique feel that features AXOLOTLS! I like how much you've added to his bio so we can have an idea of who he is without seeing much yet, and I honestly just really like the concept and ideas. On a sidenote, I don't see many amputee characters besides my own floating around...that are written as much more than the injury itself. Kudos!

My first note is the positioning of the tail. It's a bit difficult to see what it is doing; if the end is closer to us, farther, or if he is balancing on it, which I assume he is. This is mostly because the tail has an awkward, very sudden bend to it. For next time, I'd recommend employing a Line of Action so you can have a smooth, clear pose.
Next up is your detailing, which is honestly pretty nice. Definitely practice drawing hands from multiple angles - use references! Hands are still a problem for myself and so many other artists around here, so you might as well begin practicing now!
Also, keep in mind that arms are cylinders, and this should be reflected in bracelets and the like! Make guidelines on your sketches, if it helps.

My main criticism here is that the light source appears to be very inconsistent. The lighting for the hair seems to be in front and slightly up, and quite strong. Meanwhile, the light for the skin is weak and directly to the left...until you get near the neck, where both underneath the head and above the poncho is shaded. The tail's light source is all over the place and makes it impossible to judge volume.
If it helps, draw where the light will be coming from in your sketch, and keep it to the side as you colour. Shading is very important for conveying shape, and it's worth practicing.

Overall, despite this, I love this art and am quite interested in following your story! You've got a cute style that is easy on the eyes and fun character designs overall! Good job, and good luck!