There are as many different ways for a group to ride as there are ways for individuals. If riding with a group of like minded individuals interests you, look around until you find such a group.
Unless you're joining a "workout" group, chances are that most groups will be riding at a less than race pace. Most groups are in it as a sort of camaraderie thing, putting in miles together at the pace of the slowest member (with the exception of significant hills and/or strava segments:-).
Typically you can take one of two approaches: One, ride with a group that leaves you well within your abilities. Or, two, find a group that is going to challenge you. Rarely will there be a group that is Goldielocks perfect. The group I've been riding with lately varies a fair bit from week to week depending upon who shows up.
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Birth Certificate, Passport, Marriage License Driver's License and Residency Permit all say I'm a Fred. I guess there's no denying it.