If you don't press the tab key, it won't matter where your tab stops are.

A tab stop is a fact about the paragraph, not the section. Pressing the Enter key creates a new paragraph, but the default behavior is that when you press Enter, this new paragraph inherits some characteristics (including tab stops) from the previous one. But certainly you can set various tab stops for various paragraphs if you want.

If you're wanting text (left aligned), and then an equation that is right-aligned, click inside that paragraph and set a custom right-aligned tab at near the right margin is the way to go. Then type the text, press the tab key then insert the equation.

If you are trying to split the equation, that is a different story.