Notation - Sheet Music convert to .mp3

Notation - Sheet Music convert to .mp3:

I am Very new and ignorant of music terminology. However, I received some instructions to:

download & install MuseScore
import the digital file (sheet music)
convert to MIDI (IF NEEDED)
export to Audio file (.mp3, WAV)
check .mp3 file for quality (edit if necessary)

Any help appreciated!