It's easy really I will explain.
A T-Mobile Home Internet IP address can appear to be "all over the world" because T-Mobile uses a dynamic IP system, which means your IP address can change frequently and may not accurately reflect your physical location due to the way their network routes data through different towers and backend systems, potentially located far from your home; this is a common feature of mobile network providers and not necessarily a cause for concern.
There is not an infinite amount of IP addresses. IP addresses are often leased upon availability. If a company leases IP addresses from a US provider, those IP addresses will then have a US geolocation (even if the server is physically sitting in another country.)
