bbPress.org

Check out the steps outlined here https://codex.bbpress.org/theme-compatibility/

You don’t need to create a ‘Child Theme’ you only need to copy the files you want to edit to a subdirectory of your theme called ‘bbpress’ eg `/wp-content/mythemename/bbpress`

Aslo this new plugin by @MZAweb is also rather awesome to help you know what templates you should be editing.

https://wordpress.org/extend/plugins/debug-bar-bbpress/