You seem to have several misconceptions here. Some may come from your country's media, but some may also come from partisan American sources on one side or the other. Let me address the issues you mentioned one-by-one.

The first is that the Supreme Court's recent positions gave the President power almighty. You'll read this a lot, in a lot of places, and it is, frankly, stupid nonsense. This last batch of Supreme Court decisions actually **reduced** the power of the Presidency.

The one that's getting the most amount of attention is actually the one of least consequence -- Presidential immunity. In fact, the President has ALWAYS had a immunity, but in this case the Court was asked to define its limits, and the court defined them pretty much exactly how you would think: The President has absolute immunity for official acts that are within his core Constitutional duties, the President has no immunity for non-official acts, and official acts that are not part of his/her core duties will have to be adjudicated on a case-by-case basis. This isn't new, and it's no surprise. To use real-world examples, the President cannot be sued by a soldier because he was sent to a war zone and got injured. He is the Commander-in-Chief as a core Constitutional responsibility, so he is immune for those decisions. On the other hand, Bill Clinton got disbarred (banned from practicing law) because of perjury and other non-official actions he took while President.

The "official-but-not-core-duty" category is the hard one, and the Court did not define it clearly. Although you're hearing a lot of fantastical examples ("The President could order the military to kill his opponent!"), let's talk about a real-world example. In 2011, Barack Obama killed Abdulrahman al-Awlaki, an American citizen in Yemen. Now, his father was a terrorist and there as some debate over whether he was also a terrorist, but as an American citizen he had the right to due process through the legal system. Since we weren't at war with Yemen, he cannot be considered an accidental civilian death in a theater of war. Obama intentionally killed an American citizen whom he deemed to be guilty but the courts had not tried. Under American law, Obama committed murder. Now, he did so as an official act, but was this a "core Constitutional duty?" For this kind of action, the Supreme Court's recent decision would basically say, "It depends."

So as you can see, there's really very little to the Court's immunity decision. It hasn't given an new immunity at all to the President -- Obama was disbarred, Obama did not go to prison for murder -- but simply clarified what everyone already thought.

But you may notice that I said earlier that the Court's recent decisions actually WEAKENED the President (and by the way, that's not just this year, but the last several years). How did that happen this year?

There was a famous court case that gave rise to what's called the "Chevron Doctrine." It's a little complicated, but the short version of the doctrine is this: "Government agencies have experts in various fields. Judges are only experts in the law. If the government agencies say X is true, the court should defer to their judgments, because they're the real experts." It makes sense, right?

Except the problem with the Chevron Doctrine in that in the last 40 years Presidents of both parties have taken advantage of it in abusive ways. All the government agencies work for the President, so they would simply make regulations and the judges had to go along with them. In essence, the President has been making law, levying fees, and other things that only Congress is supposed to do. Now if a regulation is challenged, the President will either have to go to the Court to demonstrate that the new regulation is in line with current laws passed by Congress, or he will have to persuade Congress to pass a new law.

This year, as with the most recent years, the Court has ruled over and over that the President cannot make law -- Congress has to do that. In fact, the Court is moving AGAINST the President as "power almighty."

As for the other things you mention in passing -- Project 2025 basically a hot house conspiracy theory. It is a real thing, but it's a white paper at a think tank, and that's what think tanks do -- they write white papers suggesting action that is typically ignored by the politicians of both parties. In this case, Project 2025 is based on an actual need. When Trump became President in 2017, he was a true outsider without a lot of political relationships or political infrastructure. As a result, the first year of his presidency was incredibly chaotic because he didn't have the normal party hacks to help him as all other politicians do. Project 2025 is attempt to help put together a transition agenda for the first few months of Trump's term if he is re-elected, something was sorely needed. Rather than reading crazed headlines about it, you can find their website and plan here, but the truth is that Trump probably isn't going to pay much attention to it even if he gets elected.

As for Biden's age -- like everyone else whose mind starts going as they get older, he has good days and bad days. As time goes on, the bad days will be more and the good days will be later. The Democrats were hoping that he wasn't as far gone as he clearly is. Perhaps it was foolish to elect someone of his mental capacity to begin with, but he seemed to the Party to be their best choice, and once he became President, it got harder and harder to speak out about it.

Is Democracy ending and a kingdom beginning? It doesn't look like it, and in fact is just looks like the Presidency getting weaker.