The fire is an image (i just used a SVG I made on scratch, don't ask). The blur is something called post-processing. If you want to know what it is, it just is the process of the image being rendered. So, you can use post-processing for whatever blur or filter to make it look cool.
I use blender stuff too much ;-; I'm a real 3d modeling nerd (I literally even have a 3d printer lol)!
