There should be a page or a new tab where you can decide what Brave does after it opens. For the past 3 years, I’ve always opened a new tab before closing Brave, because when I launch the app, it’s annoying when a YouTube video suddenly starts loading right away.
Go to brave://settings/getStarted and set On start-up to: Open a specific page or set of pages - Enter: about:blank as the specific page address.
And in addition, if you wish, for the setting: New Tab Page > New tab page shows select Blank page