I did a google search on "public domain piano score sheets". There seem to be a handful of quality results returned. Check out if any of the recommendation fou

I did a google search on "public domain piano score sheets". There seem to be a handful of quality results returned. Check out if any of the recommendation found in : https://www.onlinepianocoach.com/public-domain-sheet-music.html https://www.onlinepianocoach.com/public-domain-sheet-music.h... work for you particularly the one to "International Music Score Library Project (IMSLP)"