How to edit Windows + Linux bootloader?

Question

linux

Installed two systems Windows 10 and Ubuntu. When you turn on the computer, a menu appears where you need to select which system to boot into. After the next automatic Windows update, this menu disappeared and the download occurs immediately in Windows. Can you please tell me where is the bootloader? Can it be edited? And how to return the choice of systems to boot?

Answer 1

1. Usually in the MBR of the active disk.
2. Yes, but why? Maybe you meant - edit its configuration file?
3. Google "restore grub %name of your linux distribution%"

Answer 2

Usually, if linux is installed as the second system after Windows, then grub is used as a bootloader.
There is such a graphic stray for Linux boot_repair. Used it in ubuntu.
If you have 2 disks and Linux is on the second, then it most likely created a boot partition on its disk. In this case, in BIOS / UEFI, you can choose to boot from another disk. Then you can get into Linux (but not into Windows) and use boot_repair there. After recovery, you will have the opportunity to choose which OS to boot into.
If there is only one disk, then you can make a live flash with Linux boot from it and run boot_repair there.
At the extreme, you can also configure the Windows bootloader to boot Linux.