Option 1:

From Setup, in the Quick Find box, enter Apex Settings, and then enter a value (1–600 seconds) for Default minimum enqueue delay (in seconds) for queueable jobs that do not have a delay parameter.

Option 2:

Use delay parameter in System.enqueueJob() method.

Syntax:

System.enqueueJob(queueable, delay)

delay (0–10 minutes). The delay is ignored during Apex testing.

Using the System.enqueueJob(queueable, delay) method ignores any org-wide enqueue delay setting.