how do i stop these lines that automatically appear when i try to add space? example:
little distinction was shown between a Japanese soldier and a Japanese civilian. All would die.
shiko Shimabukuro was was one of 222 female students mobilised as a battlefield nursing unit for the Imperial Army in March 1945.
The problem is not clear. Please revise your question (and title).
Two of multiple posible answers:
Select the paragraphs, choose menu Format - Paragraph… - Borders tab, and check Merge with next paragraph.
Select the paragraphs, choose menu Format - Paragraph… - Borders tab, and choose Set No Borders preset.
See more LibreOffice Help on Borders.
Tested with LibreOffice 6.3.6.2 (x86); OS: Windows 6.1
One more:
If you get a line when you type three or more hyphens (-), or underscores (_), and then press Enter, see
Automatic lines in Writer.