For custom objects, you need to enable tracking in the object details before selecting the fields to track. Let's say we have a custom object named Claim. Perform the following steps:
- Navigate to Setup | Objects and Fields | Object Manager.
- Click on the Claim object link and click on the Edit button.
- Enable Track Field History in optional features, and click on the Save button. This is shown in the following screenshot:
- Select Fields & Relationships from the menu on the left-hand side.
- Click on the Set History Tracking button, and select the fields you want to track.
- Do the same with the standard object, ...