Most modern DSLRs will do focus bracketing with a standard lens. This can allow you to take the shots needed for focus stacking, but at relatively low magnification (lenses typically won't go >1:1). So if you are doing pictures of coins with very deep relief, like ancients or high relief medals, you can take the focus stack source images with focus bracketing. You will still need to process these using focus stacking software to get the final stacked image.
Some folks have experimented successfully at using the focus bracketing capability of cameras like the T6, using the standard lens but with another objective lens attached to the front ("stacked lenses"). This is fairly advanced stuff but it can possibly take you into the territory of 2:1 or maybe a bit higher magnification.
The general method, and preferred method beyond 2:1, of doing focus stacking is with some mechanism that can move the entire camera + lens across a range of focal planes. This assumes the lens is capable of going >2:1, which few standard lenses can do. For higher magnifications, other methods like using long extensions, bellows, or "stacked lenses" are required.
Note that some recent cameras will actually do the focus stacking for you in-camera and will output a stacked image. But again this is generally only for low magnification, and is limited by the magnification range of the lens that is used.
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