Members of a group

Yes we have a function and smart service for that.

Fetching Group Members  - https://docs.appian.com/suite/help/22.2/fnc_people_a_groupmembers.html

Remove Group Members Smart Service -  https://docs.appian.com/suite/help/22.1/Remove_Group_Members_Smart_Service.html#:~:text=The%20Remove%20Group%20Members%20node,Group%20or%20System%20Administrator%20rights.

For fetch the group Member you can use the function which Ujjwal mentioned and to remove we have function as well as Smart service available.

Remove Group Members Smart Service - Appian 22.3