Is it normal to be able to unfocus your eyes?
Yep.Totally normal
Yes. Many people can deliberately relax their focus and make things look blurry, then bring them back into focus.
That’s usually just you changing how your eyes focus. Some people can do it on purpose more easily than others, and it’s generally harmless if you can refocus normally afterward.
If your vision goes blurry or double without you choosing to, or it doesn’t clear up, that’s a different thing and worth getting checked.