Step 1 – Download a DMG package from here
https://dev.mysql.com/downloads/mysql/

Step 2 – Download a DMG package from here
Click on DMG file and again you get .pkg file.

Step 3 – Start installation by clicking on .pkg and follow the installer.

Step 4 – During installation, make sure that you have captured and stored a A temporary password is generated for root.

A temporary password is generated for root@localhost: rqJoR.vdr16P
If you lose this password, please consult the section How to Reset the Root Password in the MySQL reference manual.

Step 5 –
Insert MacOS admin password for during prompt.
Start MySQL
sudo /usr/local/mysql/support-files/mysql.server start

Stop MySQL
sudo /usr/local/mysql/support-files/mysql.server stop

Restart MySQL
sudo /usr/local/mysql/support-files/mysql.server restart

Step 6 – How to verify mysql server is running or not
/usr/local/mysql/bin/mysql -u root -p

Step 7 – You must set new password first time you login to mysql else it would through following erros.

Rajeshs-MacBook-Pro:bin rajeshkumar$ /usr/local/mysql/bin/mysql -u root -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 6
Server version: 5.7.28

Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> show databases;
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.

How to set up your password for the first time?

$ /usr/local/mysql/bin/mysql -u root -p

SET PASSWORD = PASSWORD('your_new_password');
or
ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass';

More Reading
https://dev.mysql.com/doc/refman/8.0/en/osx-installation-pkg.html
https://dev.mysql.com/doc/refman/8.0/en/osx-installation.html