I was checking the link of Import and Export https://docs.microsoft.com/en-us/dynamics365/customerengagement/on-premises/basics/export-excel-pivottable
And I found this information which says we\ do changes in composite fields or calculated fields and try importing file, the updates will not take place in D365, later it says the same thing but then it says it can reflect in D365. I am unable to understand it properly. Can any one help.
If you're going to make changes and import the data file back in to Dynamics 365 Customer Engagement (on-premises), remember that secured, calculated, and composite fields (such as Full Name) are read-only and can't be imported in to Dynamics 365 Customer Engagement (on-premises). You'll be able to edit these fields in Excel but when you import the data back in to Dynamics 365 Customer Engagement (on-premises) these fields won't be updated. If you want to update these fields such as a contact's name, it's recommend that you use that view to export your data, update them in Excel, and import them back to Dynamics 365 Customer Engagement (on-premises) for changes.