How to install Linux on an encrypted disk partition with a bootloader on a USB flash drive?

Question

linux

The task is to put the Linux distribution at the end of the disk on which Windows is installed, and place the bootloader on a USB flash drive, and the Linux partitions themselves must be decrypted when booting when entering the key.
I tried to do it according to this article: https://habrahabr.ru/post/91948/
There are several questions for its author:
1) We edit /etc/crypttab - this file is not in the system after installation! but it is in the system where the encrypted partitions were created. It's a typo?
2) The article uses scripts to mount the key file from a flash drive, as far as I understand, if I want to boot the system by entering a password, then "Create a file /etc/initramfs-tools/hooks/cryptokeys with such a script" I do not need to do this, but here "Create a file /etc/initramfs-tools/scripts/local-top/cryptokeys with a script" you need to make adjustments (the question is what).
3) after all these operations, when entering the command "sudo update-initramfs -u -k all", the system cursed at the lack of free space. What is the problem? More than disk space.
Is there any more detailed step by step guide right? I have already read many articles, but nothing works.

Answer 1

1) it probably depends on whether you have the necessary packages and utilities installed
2) it is important to understand that the decryption method depends on how you encrypted the disk, so man cryptsetup will help you
3) initramfs is in /boot/ check that there is enough space, inode and partition is writable.