Any way to call a particular contact from opportunity?

[victor]

You can add Contacts in Administration > Entity Manager > Opportunity > Layouts > Bottom Panels. And make calls by clicking on the necessary phone number of a specific contact.

[Russ]

Let's say I have the opportunity, it has 2 contacts (main - client), secondary (dealer), how can I make opportunity have an option to call them (ideally), or just a client?

Thanks