Very nice image here! Good color and really great texture.
I do have one suggestion which is content based. When I think about the term "wizard training" I think of all sorts of cool stuff that would be involved in that. In my opinion, that is what made harry potter so popular. Who wouldn't want to go to hogwarts to learn about all that stuff. They made it fun! So when I see this image, it looks plausible, but it doesn't look fun. It looks like he's doing homework with an old dude watching his every move. Which is stressful!
So I would suggest making something that really invites the viewer into the world of what "wizard training" might be like. Have some fun with it. Think about the personality of both characters andn what they would be doing in the scene based on that. A nervous young wizard and an older experienced wizard who has seen it all. Very different reactions between the two.
Here's a quick paint. Use as much of it as you want. Think about dragons and runes and potions and all sorts of stuff. Make me want to become a wizard in training! : )
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