For open groups, you can see all members and view their profiles in the web version under "Show details" and "Members." In the apps, you can also find the member list under "Details" > "Members." For closed groups, only the moderators are shown; you must join the group first to see all members. More information can be found in the linked help article.
You have discovered a group that interests you and want to see who is a member of this group.
Note: For closed groups, only the moderators are displayed. You must join the group first to be able to see the member list. More information at: How can I join an existing group?
For open groups, proceed as follows:
For the web version
Click on "Show details" in the group, then on the word "Members." A list will open where you can see all members of the group. To open a person's profile, click on their profile picture or name.
For the apps
In the group, under "Details," tap on the word "Members." A list will open where you can see all members of the group. To open a person's profile, tap on their profile picture or name.