Google Apps Script onEdit clear/change cells in another sheet based on a lookup [closed]

I have a Spreadsheet that is tracking updates to knowledge base articles.

I wish to create an onEdit function where a checkbox being ticked in Sheet 2 (P15) looks up the article title from that row (C15) in column A of Sheet 1 and clears column H (Notes on update) and changes column G (Article status) to 'up to date'.

I have no experience writing Apps Script and have spent hours without much luck making any progress on the script! I would be very appreciative of any assistance you can offer.

Spreadsheet here: https://docs.google.com/spreadsheets/d/1MC0yZr_RgPmwunaiWF9eHZldY-8_ZdWnkIblNsPeFXc/edit?usp=sharing