Windows 10: How do you, do this?

My computer, is a laptop. Running, Windows 10.After creating a circle in, MS Paint. How, do you save it.As a, JPEG file. Separate, from the program?Looking at the, attached picture.You will see what I created, in MS Paint.The problem is, what I need. Is the black circle, only.Not the surrounding, white area.So when I Click, to open it. All, I see. Is a, black circle.How would, I do it. Or should I, be using. Something other, than MS Paint?Thanks for reading . . . Jerry====================================================

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