Google Tag Manager API Setup -- 2

I need assistance setting up a meta conversion API using Google Tag Manager for my website, which is built on Custom HTML/CSS. The conversion goals that I want to track are view content, checkout initiated, add payment info & purchases. Google Tag Manager is already installed on my website, partner integration is done for GTM through meta & server is sending events. The events are not being tracked on ad sets and that’s where I need help.

Key Requirements:
- Set up conversion tracking for product purchases using Google Tag Manager.
- Ensure compatibility with a Custom HTML/CSS website.

Ideal Skills and Experience:
- Proficiency in Google Tag Manager and conversion tracking.
- Experience with Custom HTML/CSS websites.
- Understanding of e-commerce conversion tracking.