Here are the steps:
1. In the Admin console Go to Apps > G Suite Gmail > Advanced settings.
2. Scroll to the Spam section, hover over the setting, and click Configure.
3. Enter a unique name for the setting
4. Check the Bypass spam filters for messages received from addresses or domains within these approved senders lists box.
5. Click Use existing or create a new one, enter a new list name, and click Create.
6. Hover over the list name, click Edit, and then click Add.
7. Enter domain name ‘abc.com’
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