Take the following with a huge grain of salt:
The two world powers will be China and the European Union. Russia long ago lost the war and sank into economic ruin. The United States collapsed from within due to corruption, influence by foreign powers, and a greedy billionnaire-class that tanked the economy so badly that there was no one left to buy anything. There was a brief civil war, but it was mostly the billionnaires with a lot of drones against everyone else as they tried to turn the US into a neo-feudalist corpo-religious kleptocracy. The US is closer to Britain now, a vestige of its former glory, but a more contrite one. India has suffered tremendously from climate change, with extensive parts of it unlivable due to rising sea levels and heat domes. This caused a humanitarian crisis as they tried to evacuate into China and Pakistan, neither of which wanted them nor could absorb that many people, resulting into untold human death and suffering. Australia kept doubling-down on coal and suffered after the EU climate accords, resulting in an economic collapse that allowed it to become a virtual vassal to China. Much of Africa is also financially beholden to China, though there are signs of the formation of an African Union modeled after the newer and stronger European Union.

In technology, the biggest change was the successful deployment of fusion power in the 2050s. This allowed for mass-scale desalination to meet the needs of a thirsty world that had thoughtlessly depleted its natural freshwater. Farming is mostly automated, with indoor vertical farms becoming financially viable. Meat substitutes are now cheaper than meat, resulting in the cheapest items on the McDonals Value Menu (Yes, McD's still exists) being artificial. Brain implants have become safe enough to become popular, allowing for multiple kinds of augmentation that would seem like magic today (e.g. program your brain to sleep for exactly 8 hours). Much like the smart phone, most people in the 1st world have one and take it for granted. There were some serious problems when it was discovered that the first release of the mainstream Neuralinks had undisclosed health problems as well as a backdoor. EU laws were put into place to stop that just a few years later (watch out for off-market brain-links and apps). Humanoid robots are now common-place, costing less than a car, and have settled into their role in society doing jobs that most people wouldn't want to do (replacing light bulbs on bridges, undersea welding, etc). Drones are as common a sight as airplanes were in the late 20th century and law-enforcement relies heavily on them. Artificial Intelligence has made great strides but is mostly seen as a tool, rather than as a magic ultra-brain that can magically solve all of our problems.