How to Center-Justify the Text When Center-Justify Doesn't Work

How do we center-justify text to be in the center of the page? I have been trying over and over and over to center-justify on the page, but it center-justifies to the right of center? I have cleaned up errant spaces to make sure the webpage sees just the text I want it to see. Doesn't work.

Also, how do I get rid of the empty lines between the lines of text (which is center-justified)?

shorespeakers.toastmastersclubs.org/

Stop using Margins and just use the center text button in the editor menu
also use Shift Return to go to next line without a blank line.

I don't know how to stop using Margins because I've never used them in the first place, although I must have done it accidentally. I can't find any icon-button which says Margins or any explanation or text on how to use them. So please provide some direction here on where to find the Margins button or icon or description.

Select formatted text then click icon indicated below to remove formatting.

Perfect! Thanks so much.