How do i turn off private browsing on my MacBook pro?

If you mean "private browsing" within a web browser, then just click the red "x" button on the browser's menubar or click File --> Close Window. If the browser is still running then press Command + N or click on File --> New Window to open a new regular browser window. Or if the browser closes completely when you click the red "x" button on the menubar, then just relaunch the browser.

If you are using a really old version of Safari, then you may need to click on the File menu and unselect "Private Browsing" to toggle Safari back to normal mode.

If the browser always launches in private mode, then go into the browser's preferences and uncheck "private browsing mode" which is likely in the browser's privacy section of the preferences/settings.

If this isn't enough, then you need to provide more information such as the exact version of macOS you are running and the web browser you are using including the browser's version number.