Explanation
The users are assigned different profiles and page layouts, which determine the fields they can see and edit on the opportunity record.

The contact record component that must be present so users can see a visual representation of their emails and phone calls with a contact is the Activities Timeline. The Activities Timeline shows a chronological list of past and upcoming activities related to a record, such as emails, calls, meetings, tasks, and events. Users can see the details, status, and attachments of each activity, and also create, edit, or delete activities from the timeline. Activity Capture is a feature that automatically syncs emails and events between Salesforce and email and calendar applications, but it does not show a visual representation of them on the contact record.
Salesforce Inbox is a product that enhances email and calendar productivity with Salesforce integration, but it also does not show a visual representation of activities on the contact record.

Explanation
The best place for GCC's Salesforce associate to go to collaborate with others on solutions that might resonate with GCC users is to ask a question in a Trailblazer Community Group. A Trailblazer Community Group is a forum where Salesforce users, partners, customers, and employees can connect, share, and learn from each other. There are groups for different topics, regions, industries, and roles. The associate can join a group that is relevant to their needs and interests, and post a question or a discussion to get feedback and ideas from other members. Exploring documents in Help and Training or searching for modules in Trailhead are also useful ways to learn more about Salesforce, but they are not as interactive and collaborative as asking a question in a Trailblazer Community Group.