Observed in close-up, the smallest planet in our solar system looks like the far side of our Moon, except that it is almost twice as big.
Unfortunately, we will never have such magnification from Earth, but with a powerful wide aperture telescope, you can see the phases of Mercury through the eyepiece.
Wait until the Sun is completely set before observing Mercury, otherwise it will be drowned out by the intense brightness of the Sun due to its proximity to it.
The planet Mercury turns very slowly on itself: a mercurian year (its revolution around the Sun, about 88 Earth days) is worth 1.5 times a mercurian day. A rotation of Mercury is therefore equivalent to 59 Earth days.
Select another planet to observe with a telescope
Image credit of Mercury: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington / Public domain