Edit Salesforce Page Layout of Opportunity Contact Role

In order to add newly created field while creation of opportunity contact role ,User have to modify the Multi Line layout of Opportunity Contact Role object

1. From Setup, open Object Manager and select Opportunity Contact Role.

2. Click Page Layouts, then select the layout you want to edit.

3. Click Edit Multi-Line Layout at the top of the page.

4. Add the desired custom fields from Available Fields to Selected Fields. 5. Click Save.

Note: This change applies to Lightning Experience only. Custom fields added to the Multi-Line Layout are not editable in Salesforce Classic, though data may be visible in related lists.