constructing lines parallel to an existing line

I am a new user but not new to CAD.  I want to be able to construct a line or an array of lines parallel (offset) from an existing line and really would like to have someone help me with the proper keystroke sequence.
I seem to be able to construct a single line if it is offset (parallel) to the existing line and the offset is in the positive direction.  But I cannot figure out how to do the offset in the opposite (negative) direction.  I also cannot figure out how to construct a series of parallel lines all the same spacing apart whether they are in a positive or in a negative direction.  
I am in my 80's and want to learn LibreCAD - so far so good but I am pretty well stumped on parallel line construction.
It would be most helpful if you could provide me with the keystroke sequence to make this work ---
i am continually getting syntax errors.

Thanks for your help --

Jerry  Weaver

Try https://www.youtube.com/watch?v=duQ_9N-JfzA

After selecting the line and starting Offset (or use Line > Parallel for a direct parallel tool), enter your spacing distance (positive, e.g., 10). In the options dialog (top of screen), set Number of offsets to your desired count (e.g., 3 for three parallels). Hover on the desired side (positive or negative direction) to preview the array, then click to create them all at once. Direction flips based on cursor side; use negative distance for the opposite way.