Okay here we go.
The image quality is bad. Like, it's just bad. It's best to find clean images for avatars, anything else just doesn't look that nice.
The aspect ratio looks slightly warped. Never stretch images when resizing.
The positioning on the avatar is decent, although I feel like he could be slightly more to the left.
The glow is bad. That's just not the way you do glows. Most image editors have plugins/filters for glows on transparent bitmaps, which is what you should be using. If you're insistent on having a radial glow from behind him, give it more feathering.
I have nothing against names, but that name is terrible. The positioning is kind of awkward, it's too big and bulky, and the font is horrid. I don't recommend using names in avatars unless you really know what you're doing.
And that's about-- oh wait, there's a border.
....Yeah, no, just stick with a simple 1px border, or get someone to teach you fancy borders, or just don't use anything. I don't really even know what you did to get that border.
So yeah, that's what I have to say about this. I guess it sounds pretty harsh, and there are a lot of bad points, but in reality your avatar isn't
terribly bad. It's just... regular bad, you know? It's not as bad as a lot of avatars out there, and it certainly has a lot more work put into it than most, so you just have to work on those points and it should probably turn out better. You did okay as a beginner.
As an additional note, the black background behind the character and glow is really plain; you could try to add in some sort of background, or have it transparent.
Here's one of my avatars, so you can see the proper way of doing things. It's one of my best ones, and I at least think it's pretty good.
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I just started using PS 
soo im kinda new too it 
