The piece sounds very 'simple'. On this page you'll find that simple version. But there are other notes in the piece which I don't understand yet how to play them.
As in measure 22. Is it with or without the e's? I can't reach the bass notes properly, can I leave them?
About the left hand fingering of the measure 17 fragment:
These are two options to play the notes of the C and Em chords in measures 17-18.
The second way my hand is switching earlier to the place of the next chord by using another finger: