score writing from electric keyboard

Yes, if you press several notes at once, MuseScore will notate them all. But it can't do magic - it can't figure out which notes are played by the left hand versus the right hand, can't figure out the optimum way of notating things if you play notes of different durations at the same time, etc. So if you were hoping to just play the piano normally and have everything translated automatically to readable sheet music, that sort of AI technology doesn't really exist yet. You can try recording into a sequencerm saving a MIDI file, and importing that, and then MuseScore will attempt to make guesses about the sorts of things I mentioned, but they will be just guesses, and except in the simplest cases, the results will seldom be usable without considerable editing.