Create a New User and Grant Permissions in MySQL

mysql -u root
# mysql -u root -p

CREATE USER 'newuser'@'localhost' IDENTIFIED BY 'password';

GRANT ALL PRIVILEGES ON * . * TO 'newuser'@'localhost';

ALTER USER 'newuser'@'localhost' IDENTIFIED WITH mysql_native_password BY 'password';

FLUSH PRIVILEGES;

exit

References
https://www.digitalocean.com/community/tutorials/how-to-create-a-new-user-and-grant-permissions-in-mysql