Query re IPv6

Hi, I have a vast amount of experience in networking (and an expired ccnp which I’m working on recertifing on) but for various reasons, I have never been exposed to IPv6 in real life. In my country, it is not really used. even ISPs still issue IPv4 global addresses. I am going through various videos re IPv6 but one thing never is made clear, with regards to global unicast addresses how does one obtain them? Do you need to go to the regional internet address authority (for example RIPE)? How are real IPv6 networks implemented in the enterprise (do they use the concert of unique local addresses and NATv6 to translate to a global unicast address at the internet edge) ? and if a network is fully deployed using global unicast addresses I would assume a process of subnetting also applies as I see it extremely wasteful to deploy a /64 address on a point-to-point wan link for example.