BuddyPress.org

Buddypress pages are not listed in the admin. To edit those you need to make a child theme.

https://codex.buddypress.org/how-to-guides/building-a-buddypress-child-theme/

If you want to make additional pages you can via admin like you do any normal WP blog. Admin >> Pages >> add new

If you know how to make wordpress page templates you can create anything you want and then in admin >> settings >> reading choose your custom page as the static front page.