Can’t remove topbar menu

I want to have the bigger centered logo for mobile. I can’t use the “Topbar and Header Menus, logo centered” option because I don’t want to have the topbar menu. I can’t remove the topbar either. If I delete it, all my pages show up in that space published or not as shown in the screenshot.

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How can I either remove the topbar or get my logo centered and bigger on mobile without using this menu?

Thanks!