I would like to have a website that is loaded fast from any point in the world. From my understanding, you need to take advantage of the data center "regions" at places like Google Cloud or AWS. That's as far as my understanding goes.
What is missing is how exactly to implement it (at a high/diagram level here, not at the code level).
For example, on Google Cloud for a specific "project" you have the choice of IPv4 or IPv6, of "Premium" vs. "Standard" ("Traffic traverses Google's high quality global backbone, entering and exiting at Google edge peering points closest to the user." vs. "Traffic enters and exits the Google network at a peering point closest to the Cloud region it's destined for or originated in."), and of Global vs. Regional. If you select IPv6 you are limited to Premium. If you select Global on IPv4 you are limited to Premium. I am not sure how this works, not at the level of detail of Google's specific system, but what generally is going on here. I don't see how a "global" IP address can be better than a regional one, since the regional one is closer to the request source.
On AWS, they don't have a "Global" option, all IP addresses are IPv4 and they are regional.
That was just some background for the main question.
My question is how to architect a system to take advantage of regional data centers. Just generally, at the IP level. I am wondering how it goes from my domain to the regional IP address. Or if it is like Google Cloud's "Global" IP address, how you could then integrate regions into it. Or if that's backwards, how to conceptualize of this. I saw the diagram below, but it only explains how a domain is mapped to a single region-independent IP address. I don't see how regions are actually implemented / come into play.
Basically I would like to know at a high level how I should organize my IP addresses and servers to take advantage of regional data centers. So far my thinking is of having servers in different regions with their own copies of data. But then I get lost when thinking about IP addresses and domains. If I use the AWS model, it seems I reserve an IP per entrypoint server per region. But then I don't see how the domain name figures out which IP/region to select. If I use the global Google Cloud model, I don't see how I can add regional servers.