Root is a superuser and can create users.

LASA said in the title that it has the right to create.

U 1 only has query permission.

U2 has insert permission (U2 can use the create user command, because this command is equivalent to inserting data into the mysql.user table, such as:

Insert? Become? Mysql.user (host, user, password)? Value ('localhost',' user 1','123456');

The second question:

Look at this picture, please.