How to implement Create trigger in next gen sales

Summary:

We have one create trigger in childRevenue which defaults value from opportunity there.

Content (please ensure you mask any confidential information):

We have requirement to show some of the fields in childRevenue based on the field we are defaulting from opportunity and we have triggered that logic in Create trigger. And some fields LOV are dependent on that fields so the Lov's are not showing there.

As create trigger are not working in next gen sales so how can we implement this logic.

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