BuddyPress Integration

Hello

I am in the process of following the instructions at https://www.designwall.com/guide/dw-question-answer-plugin/buddypress-integration/ for integration of BuddyPress with DW Question & Answer. As I do not host my own site, there are issues about me editing my functions.php file or even creating a child theme functions.php file. I would like instead to add code using the Additional CSS area in my dashboard. However, when I copy-paste the recommended code “include_once get_template_directory().’/buddypress/bp-custom.php’;” into this area, multiple errors are reported as follows:

Expected LBRACE at line 5, col 14
Unexpected token ‘get-template_directory(‘ at line 5, col. 14.
Unexpected token ‘)’ at line 5, col 37.
Expected INDENT at line 5, col. 39.

I am in turn advised of the following:

There are 4 errors which must be fixed before you can save.

Update anyway, even though it might break your site?

This leaves me in doubt as to whether I have the correct code.

I would be grateful for advice on how to edit the code so that it is accepted in the ‘Additional CSS’ box as an alternative to editing the ‘functions.php’ file.

Many thanks!