The headli e and body copy on printing gives me labels too large for the purpose
Don’t compare screen size, even at 100%, to what yu will get printed unless you have set up your PC specifically in every respect. Of course you could zoom to match the width of the paper.
I suggest turning on rulers in Writer so you will know the dimensions of what you are designing. If rulers aren’t visible then in the menu click View > Rulers > Rulers and also View > Rulers > Vertical Ruler