In WordPerfect, block protect is block protect — you highlight a block of text and protect so it all shows up on the same page.
Is Word that simple? Oh, no. Microsoft had to come up with TWO different versions of block protect: Keep Lines Together and Keep With Next (accessible from the Format, Paragraph menu):
So, what’s the diff? And how do you know when to use one or the other?
Keep With Next keeps two or more lines of a single paragraph together. In other words, it’s keeping a block of text that doesn’t have a hard return/line break within the block all on one page.
Keep Lines Together keeps lines from separate paragraphs together on a single page (e.g., a heading and the first few lines of a paragraph). It’s for a block of text that has one or more hard returns/line breaks in the middle of it.
If you’re confused about which to use, you can check both boxes. It’ll work just fine.