How to migrate production WordPress to Localhost

Out of the box Mamp runs different ports. Are you able to change it to port 80 or are you restricted to doing that for some reason?

If you are able to, change the port to port 80.

mamp->preferences->ports and change Apache port to 80 and then restart
services

UPDATE: For the wp-admin that will be because in your database your site and homepage urls are set to the live version.

You can override it in wp-config.php by adding the following to the bottom of it:

define( 'WP_HOME', 'http://localhost' );
define( 'WP_SITEURL', 'http://localhost' );

OR if you want to edit directly to the database. Go into your local database and go into wp_options and change the options in there for wp_home and _wpsiteurl