I really appreciate your comments.
I'm using Pyxel edit and I feel fine with this SW. I downloaded a high saturated palette from Lospec because I love Dead Cells art, I hope some day I would be able to do something similar 
And talking about HW I have a digital tablet but I feel better using keyboard/mouse, I don't know If it's worth forcing the digital tablet use for better performance in the future.
This is the best welcome I've ever had on a site or forum 
No problem! Really, the best thing (and the thing you hear the most) is just keep at it, while overused in advice it IS true. If you ever feel stuck on palettes or just cant seem to make your own one work out just right try websites that offer free palette creations that can help you pick or a site that has others that you can choose from! If you use Aseprite it also has a handful of palettes built in that are really fun to play around with! While not able to post them here, you can always try your hand at sprite edits, too, mostly for light source practice and stuff like that, if you were to find that easier!
Sorry for the paragraph, but I hope to see more from you and watch what you do! ^^/
It's not bad at all! You could try to add some more colors to your outlines (like using the darkest blue on his left hand shoulder) to really make the light source noticable. You could also narrow down your color count as there's a few spots where the colors are a little unnecessary imo, like using the same greys for the spots in his hair or the same whites from the buttons, though this isn't that big of a deal. (You can use this to check your colors and maybe see what I mean because I'm not good at explaining: http://yanrishatum.ru/pj/ )
For a first go at it, it's a great job! You can really only go up from here~
I use my tablet to sketch out some things because it feels easier to do that than try and freehand it with my mouse, but it's up to you. Some people do their entire pixel art/sprites with a tablet, some don't use it at all
It's up to how YOU feel comfy working, tbh. As long as you're having fun with it you could do it with your feet or whatever LMAO
Haha, I'm glad! I was hoping I wasn't coming off too strong or anything 😅