Change buddypress 'groups' to 'classrooms'

Hello! I am trying to change the label 'groups' to 'classrooms'. I have read many articles (For example, I have read this: https://codex.buddypress.org/getting-started/customizing/customizing-labels-messages-and-urls/ ) including support tickets here on Wpmudev but I dont understand most of it. Could I have a more detailed explanation to help me. For instance, how do I change the links in the buddypress navigation menu to read 'classrooms', instead of groups?