On a Dataverse table, you can use web service rules for these purposes:
Validate data: Using a web service, you can validate if a new or changed field value in a Dataverse table matches a value in another internal or external source.
Validate and set data: Using a web service, you can:
Validate if a new or changed field value in a Dataverse table matches a value in another internal or external source.
Get a field value from another internal or external source and set this value in a Dataverse table.
Before you can set up a web service rule, set up the web service to be used.
This flow explains how to set up a web service rule.