big problem repair windows

You haven't actually stated definitively that your PC won't boot to Windows. From what you say I will assume it doesn't.

There's no indication in your post as to what led to this failure.
Before attempting ANY repair you need to check the drive.
If the drive has failed, your first priority is to recover what you can that isn't already backed up.
If it has, the less you use it the better- and the last thing you want to do is to write to it.

I hope you already have comprehensive backups.

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how to find the specific window version of the computer that doesn't work ("broken computer")

How DO /CAN you find the version?

A good approximation is to browse to any system file and examine its properties. E.g.

e.g. by booting from a live boot disk etc.

Were you to search on line you could find a more complicated way to determine this accurately using offline registry editing.
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and use usb drive to "repair" or reinstall windows while keeping on apps and all things

If your PC won't boot, you can't do an in-place upgrade repair install.
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what other options are there except this?

If you had been using 3rd party disk imaging routinely and regularly as is endlessly recommended here, and you had an image of all your O/S partitions - or even just your Windows partition- you could have restored that image and be back as you were when you created it - even if your present system disk had failed and you had to replace it.

Without that - could be a painful lesson learnt the hard way.

And thank you for your reply.

I suggest again your first task is to CHECK THE DISK.
E.g. using Crystal Diskinfo (free) - portable version available.

You can do that in at least two ways.
a. Remove and connect the disk to a working PC (best as a USB disk/external disk) and so check it
or
b. Create a live boot disk (Google if unsure) using another PC (note - this is NOT a Win 10 install disk); boot your problem PC from that. Probably on the live disk you'll find a suitable program to use.

"If your PC won't boot,"
computer boots to "boot manager"
and to "bios"

and to "usb"
it doesn't boot to computer
don't know if that counts as "If your PC won't boot,"

To clarify for you (and it's in the tutorial)
you can only do an in-place upgrade repair of your Windows installation if you can boot normally (i.e. log in and see the desktop).

I.e. you must be logged in to start an in-place upgrade repair install.
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a usb with this iso installed cannot repair a computer with a different specific version of windows?

You seem confused as to what you can do with a Win 10 bootable (USB) disk.

Booting from one lets you do at least these things:
a. Install Win 10
b. via 'Repair your Computer' to Advanced Startup Options you can
- use System Restore (if you have a restore point) and your registry etc are basically sound.
- run Startup Repair
- boot to command prompt

c. If you can boot normally (see above) then once logged in you can used the bootable disk to start an in-place upgrade repair install by browsing to Setup.exe on that disk.

You cannot use it in any simple way to repair a damaged Win 10 installation automatically otherwise.

The only possible options here

boot computer from usb drive
and use usb drive to "repair" or reinstall windows while keeping on apps and all things

- System Restore
- Boot to a command prompt and run DISM as a suitable offline command
Use DISM Offline to Repair Windows 10 Image (2 Ways).

And again, thank you for your reply.


Booting from a Win 10 install disk and choosing to install Win 10 will create a new installation.

Look:
Clean Install Windows 10
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"repair your computer" goes to "advanced options"

computer goes to Windows Recovery Environment that has this "advanced options"
what's the point in going to "repair your computer" if boot up from usb?
or what's difference in going to "advanced options" via usb
is there a difference between 'Startup Repair' in either way, failed both ways

These options are limited and specific.

They are not a magic wand to somehow fix a broken installation or a failed or corrupt disk or one laden with malware etc.
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computer doesnt boot into windows (aka: login to windows user account on computer)

"bootable disk" to start an

is that "bootable disk" about the usb drive with windows iso on it
that has been talked about in this thread, or about a different "bootable disk" like a storage drive

Here are some of the types of bootable disks:
1. A Windows bootable disk - can install Windows, has limited repair options, boot to command prompt.
2. A live boot disk- boots to a version of Windows pre-configured with lots of utilities to help you deal with unbootable PCs at skilled level.
3. A boot disk you've created from some 3rd party program.
- could be a partition manager, data recovery, AV etc etc...


Now, perhaps it's time you checked your system disk.