If you're using WP Job Manager plugin and you want to add an opening hours field to your locations, this plugin will give you a helping hand.
A new field called Opening Hours is available for all of your listings. You can only display the schedule inside of a widget through Appearance → Widgets area.
Install WPJM Opening Hours either via the
WordPress.org plugin directory, or by uploading the files to your
/wp-content/plugins/ directory