As long as we're being specific...
While the possibilities and variables are numerous, consider the following. South America will escape largely intact, its dictatorships rocked but still in place after the bombs fall. Pinochet, Bignone, and Figureoua will comprise the ABC powers and likely come together as a loose bloc with the rest of South America following their lead. Central America, Mexico, and the Caribbean outside of Cuba and Puerto Rico will be largely intact (adios to both). The Bahamas will be bathed in radiation from strikes on Florida and Texas but its infrastructure will be initially intact. More likely than not the region gravitates into the ABC bloc eventually with Mexico becoming a northern Hemisphere power player with many Americans who were able to escape the worst and tourists who happened to be on vacation endong up permanent residents. Perhaps the very irradiated Bahamas absorb refugees from the former US as well.
If New Zealand is hit, it likely stays on the North Island with Wellington getting the brunt. While technologically thats hurts the country, there are enough horses and livestock that the country will survive. More likely than not they scavenge what technology they can and go into a deep isolation save for key partners like Australia. Think Bakufu Japan's foreign policy with a 1920s tech level. If Wellington survives the country will rebound more quickly with a tech base closer to 1945.
Australia loses two to seven sites, each a profound loss but even with Brisbane, Sydney, Melbourne, Perth, Pine Gap, Canberra, and Townsville out the country can rebound. Tech levels will vary from 1800 to 1930s but expect a warm shower to be a luxury in most of the country for two or three decades. While a rapid organization of the hinterland and smaller cities is possible, more likely there is struggle over everything from water to gas. Road gangs may form but the desire of most people to avoid outright anarchy will mean cops becomes a lot more powerful in real-world terms, especially in the larger cities that survive. Life here will be hard and deadly but then in a land where seemingly everything wants to kill you...
Hawaii loses Oahu and maybe Nihau/Kauai as well, but it will survive as a very unique culture clash of Anglos and locals who have to work together to survive. If they don't they almost all perish.
Europe is a graveyard by and large, Switzerland becomes the new Shangri-La but likely isolates itself quickly from the outside. Perhaps surrounding areas with something to offer join in but they will not be forgiving to those who try to intrude on Fortress Alpine, otherwise Iberia, southern France, and parts of Italy fare better than the rest. Which is to say more than 1/4 of the prewar population may survive in the 'lucky' areas. This is a continent where the living may envy the dead, especially in Germany, european Russia, and the southern UK.
Japan is much the same way with Hokkaido, southern Kyushu, and Shikoku faring better than the mainland. Expect a new Bakufu equivalent with a lot of anti-American and anti-Soviet sentiment. They will survive and carry on but at a terrible cost, perhaps with subways repurposed into domiciles in some areas.
Siberia, Canada, and Alaska are no-mans-lands with a few enclaves of civilziation against a backdrop of overwhelming wilderness and seemingly incalculabke devastation. Radiation will linger but few people will be alive to see its effects. At whichever Soviet cities survive expect a government to begin pulling together as soon as they are able, but with very limited success for several years.
China is hard to predict, they may survive largely intact or the Russians may figure to take them out lest they push into Soviet territory. Hard to predict.
India and Pakistan initially survive with few relative casualties but eventually neutralize each other as potential powers due to a war. Pakistan loses but India doesn't win, instead shattering into a dozen states that talk reunification as they scheme to be the last one standing. No one wins but everyone loses.
Israel and the Middle East are simply gone, the only victors are the vultures, fungi, and carrion eaters. Survivors here are few, well-armed, and have no qualms about continuing ancient feuds.
Southern Africa degenerates into racial violence and may crack down or disintegrate. But the RSA has nuclear weapons and delivery systems. Expect civil war in a nation that might otherwise have led recovery efforts worldwide. North Africa is toast, and Nigeria emerges as a power in its own right. Oil becomes key to technology and even more valuable...eventually.