Joomla view - Instruct me how to change the default sort order

Hi
We have a bespoke Joomla component for selling training courses at https://www.wedotraining.com/. Using the component (com_wedo) in the back-end we can see all the courses (com_wedo&view=courses).

The sort order can be adjusted using the drop down selector at the top right easily enough (see attached screenshot). The default sort order is 'ID Ascending'. We would like to change the default order to 'ID Descending' (both those options are available in the dropdown selector).

Rather than have this change implemented for me, this job is for you to instruct me how to do it. I believe is is something like:
- populateState($ordering = 'a.name', $direction = 'desc') -

I would like to know where the files are and what code I need to change.

Thanks
I will arrange FTP, Super Admin, server access to a demo site for you to implement the changes. I can then implement the changes to the live site per your instructions .

This job is per hour. Please indicate how long you think this will take.

NB - PLEASE DO NOT BOTHER PASTING A GENERIC BID!
Any pre-scripted/pasted/template type responses will result in immediate refusal of a bid. I will not read them so please do not waste your time. Specific responses illustrate that you have read my spec. carefully and understand the job (sorry I get so many of these spam type responses).

Thank you for taking the time to read and happy Friday everyone!

Thanks

Andy