In general, I decided to install Ubuntu on my computer, I prepared myself, read the instructions a dozen times, preallocated space and so on. However, after running the Ubuntu installer, it behaved differently than described in the instructions from the official website: in particular, did not ask which partition of the disk it will be installed. When installing, I selected the item "install next to windows" and other prompts such as "whether you want to run other OSs in the future" answered positively. As a result, after installing the distribution, the GRUB bootloader menu does not contain a Windows item, which for me personally turned out to be at least unpleasant. I read several forums, everywhere there are instructions for restoring the Windows bootloader by manipulating the installation disk. I’m not very happy with this perspective as I don’t have access to the Windows installation disk at the moment. There was also talk about the need to edit the GRUB configuration file, but we could not find any sensible instructions on this topic.
By the way, all Windows directories and partitioning into volumes remained, including all the contents, which clearly indicates that the axis was not deleted (I hope).
Waiting for answers, thanks in advance!