How can you make it so that every 24 hours the database is reset. Meaning that after a day all the values or data in the database are gone. Yuri help!!

How do I create a splash screen. Like when opening the app their would be a page that loads for about 5 seconds and would have a logo or image with a loading circle. after the 5 seconds the splash screen should disappear and users should see the log in page.