MuseScore provides a number of learning resources to help the new user get started.
When you run MuseScore for the first time, the Startup Wizard appears to help you set up some basic features of the software. One of these features is called Tours, and, as the name suggest, gives you a guided tour of the program.
This will allow the Tour to run when the program opens, introducing you to the main features of the user interface.
Currently offered tours:
The interactive Getting Started score is a practical introduction to the basics of entering a score. When you open MuseScore for the first time, it will be displayed in the main window of the Start Center: just click to open it. Follow the instructions written in blue, and you will be led through the basic steps of score writing.
Note: If you don't see the Getting Started score, you can find it in the right hand panel of the Start Center. Click the right or left arrows to browse through the options until it appears.
MuseScore offers a full set of instructions videos, each covering a specific subject. You can access these videos in several ways.
In the Tutorials section on musescore.org you will also find tutorials on more specific topics (e.g. MuseScore Drumline).