Let's read the two commands that start almost every new MySQL project.
CREATE DATABASE IF NOT EXISTS school; creates the school database if it doesn't already exist. Query OK, 1 row affected is MySQL's confirmation that the command succeeded (that phrasing is a leftover from MySQL's internal bookkeeping no actual "row" of data was touched).
SHOW DATABASES; then lists everything on the server, and you can see school now sitting alongside the standard system databases MySQL ships with.
If you ran CREATE DATABASE IF NOT EXISTS school; a second time right now, you'd get the same Query OK response with no error that's the entire point of IF NOT EXISTS, and it's why real setup scripts almost always include it.
From here, the very next command in a real project would be USE school; followed by your first CREATE TABLE which is exactly where this course heads next.