Peacock allows three streams at a time. This article explains your options for profiles, account sharing, and Peacock device support and usage.
Check who is watching your Peacock Streaming Account
The maximum number of people who can watch Peacock at the same time, on the same account, is three. This is true regardless of the type of Peacock subscription you have. All Peacock subscriptions have the same three-person limit, and there is no way to increase the number of streams allowed on your account.
In this case, "person" actually means device. That is, Peacock's actual limit on concurrent streams is based on the number of devices using an account at any given time.
Peacock's Terms of Service do not allow you to share your password/subscription with anyone outside your household. However, this policy is generally not enforced.