Help setting up GA4 Enhanced eCommerce Tracking via GTM

Here is our development site:
https://chhl01mstr64s4xinte.dxcloud.episerver.net/

It's built-in Optimizely but I'm a developer and would like to set up eCommerce Tracking via GTM without any plugins used.

I would like instructions on any code changes I would need to make to set up:
view_item_list
select_item
view_item
add_to_cart
remove_from_cart
view_cart
begin_checkout
purchase

Open to looking at server-side tracking too :)