Hello ZoomVicky and welcome to PSG.
Let me see if I can help you out.
Open your image and duplicate it.
No we can convert the image into a smart object. In order to do this, right click the duplicate layer and select "Convert to Smart Object".
Highlight/Select the newly minted Smart Objects Layer and duplicate it.
Yo should now have an original and two SO layers. Turn off the original layer.
Always work non-destructively by using a layer mask.
First Use whatever tool or method your comfortable with to make a selection of the boy and his hand.
Next, you want to add the selection to a layer mask.
Click on the top layer to Highlight/Select.
Click on the "Add Layer Mask" icon located at the bottom of the layers panel.
The mask should look like this.......
If you turn off the middle layer, it will look like this.....
Turn the middle layer back on and highlight/select it by clicking on it.
Go to FILTER > BLUR > GAUSSIAN BLUR...........set the blur for the background to your liking. Since we turned this into a SO, we can always come back and adjust the blur if we like.
Next, you need to add a color fill adjustment layer. On this same layer as above, go to the half moon icon located at the bottom of the layers panel and select the SOLID COLOR.
This will add a solid color adjustment layer above the middle layer and will open the color picker. Choose a nice yellow color. Set the blending mode to SOFT LIGHT and reduce it's opacity to 80%.
Should now look something like this......
Next we need to add the black outer glow.
Highlight/Select the top layer that has the layer mask.
Double click in the body of the layer to open a layer style and select outer glow........... or, you could go to LAYER > LAYER STYLE > OUTER GLOW.
In outer glow, select black as your color, set your blending mode to normal, size to about 60px, and the opacity to around 50.
Should now look like this..........
Almost done.
If you want to brighten the boy, you need to add a Curves Adjustment layer and clip it to the top layer.
Go back down to the half moon icon at the bottom of your layers panel and select CURVES.
This should open a window like this..........
First click on the square icon with the downward pointing arrow. This will clip the curves layer to the top layer. This means that it will only affect that layer.
Next, adjust the curve upwards from the center to a brightness that you like.
You should be done!