Hi,
As per my understanding, when you pick ABC Corporation in the form (of an Entity X), you would like to copy some details from ABC Corporation's record to the record of Entity X.
I am assuming, Corporation is a lookup on the form (lookups are a reference to another record).
I will explain this using the following scenario:
When I select a Customer on Quote, the address should auto-populate (copied from customer record).
There are 2 common ways to achieve this:
- Relationship Mapping: quote has N:1 relationship with Customer entity. We can define Relationship mapping between Quote and Customer entity and copy data on Quote. To configure mapping, look at the following:
https://readyxrm.blog/2017/02/01/dynamics-365-entity-field-mappings-explained/
However, relationship mapping only works when you create the child record form Parent form. For example, when we create a Quote from Account (customer) form.
- Processes: we can configure processes to trigger on an event to do some tasks. In this case, we can configure a real-time process (often called workflows), which triggers on Create or Update of your entity's record and updates data from the Corporation record.
These are the steps to create a process:
- Go to Advanced Settings -> Processes.
- Click new to create a new process.
- Select the following configuration and click ok.

- We trigger this process on the creation of Quote and when the Customer lookup is updated. We add an Update Action (step) to Copy Address from Customer to Quote.

- Here is the Update step configuration:

You can see we are copying Customers Address information to Quote. We can copy any information from a lookup as per the need.
Once activated, this process will execute (real-time) when we select a Customer (in your case it could be Corporation).
I hope this gives you an idea of how to achieve this. Exact steps could vary based on your needs and environment.
Furthermore, you would be needing a System Customizer security role to this configuration.
Best,
Wahaj
(if it helps, mark it verified)