A Mighty Fortress Is Our God by Martin Luther, for piano. Easy level, about 2 min to play. A free, public-domain score: open it in SheetScroll and the page turns as you play.
The first half minute, played from the score by a computer, not a recording
From PDMX (Long, Novack, Berg-Kirkpatrick and McAuley, 2024), CC BY 4.0, converted by SheetScroll; the score dedicated to the public domain (CC0) by its MuseScore uploader
The free sources hold 2 copies of this score; SheetScroll publishes the best one.
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