Configure the business hours for all the support team to make them available to serve the customers. We can also make business hour field available on the case page layouts. This sets the available time for the support team to work on cases
Setup > Company Profile > Business Hours
Business Hours Page > New Business Hours
Business Hours Name: Test Business Hours
Use these business hours as the default: To set default business hours for all the cases.
Active: Allow users to associate the business hours with cases, escalation rules, milestones, and entitlement processes.
Time Zone: Select the time zone.
Business Hours: Set the business hours.