How to create an effect like on this site https://www.canva.com/?

Question

JavaScript

https://www.canva.com/ on this site the background is blurred when you move the mouse, a circle appears that "erases" this blur.
Is it possible to do this knowing only html css and js at a basic level and how to do it?
I briefly studied canvas, they mainly show the outline of lines, circles, triangles, etc. But I can’t find information about such features, advise a good source on which you can learn the noble canvas chips and do something like that