Librecad is an open source drawing program to make two dimensional drawings.
You can do your first experience with the with the aid of the user manual (https://librecad.readthedocs.io/en/latest/) , however nothing is written about how to setup your workspace.
But if you think to make a lot of different type of drawings (f.i. electrical schemes, mechanical or building drawings), it is recommended to make a good setup your own workspace.
In this document you get some practical guidelines.