BuddyPress.org

@socially2020 it will be your theme-specific customization task.

@socially2020 as nested comments or you are looking for similar styling?

@socially2020 You will have to code for it
at xprofile_avatar_uploaded action, you can hook notification
for ref, you can check https://codex.buddypress.org/developer/function-examples/bp_notifications_add_notification/