how to export a game step by step?

After a game is over, I'd like to export it on my Pc, tablet, smartphone. But I don't know how to find its PNG file...Could you help me please? Thks

after the game is over you can click on study and you can get the png from a study, if you have any questions, feel free to send me a message

Click on Analysis board below the move list and then FEN & PGN tab below the board.