Nuclear is bad for the climate

Nuclear has basically no CO2 output, so that's wrong.

has the worst waste humanity can produce (...) we do not have the tools to plan for that kind of timespan AT ALL, everyone saying he can build structures safe for that time is lying or mislead.

There's one super simple method. We just don't use it, because it flies in the face of regular waste disposal and remediation methods: Grind up the waste, pour it in concrete pellets, mix it with the mining tailings and chuck it back into the hole you found it. You're basically restoring the status quo if you do that. The only reason we don't do this is because legal frameworks don't allow this. In a way, long term geologic storage is exactly this. Drill holes in the ground, stuff the spent fuel inside, cap the hole. You can do that far easier, but it's legally not allowed because people like greenpeace (and you) think radiation is magically dangerous.

And nuclear is hard and expensive to build. There is not a single reason someone to build reactors,

There are 62 nuclear plants in china right now, most from the past 10 years, and there are 34 being built now, with 150 planned. They are basically disproving every "Expensive and slow" stereotype, simply by doing what nuclear proponents have been saying since the 50's: "Build more, and it'll get cheaper". It's the exact same way solar, wind and batteries are getting cheaper. China builds nuclear because it hugely improves air quality, because the alternative is coal.

We used to be able to build nuclear plants quickly and affordably in the west too, but eeeeeveryone stopped doing it when chernobyl happened, which was basically specifically built to explode.