Find Windows 10 ISO build version by command prompt

Open cmd with admin rights:

Look in you iso and depending if it a dual boot or single you should have subdirectories or not

ex where F is you drive letter of mounted iso or path if extracted

If you have install.esd in your sources folder:

For dual iso:
dism /Get-WimInfo /WimFile:F:\x86\sources\install.esd /index:1
or
dism /Get-WimInfo /WimFile:F:\x64\sources\install.esd /index:1


For single iso:
dism /Get-WimInfo /WimFile:F:\sources\install.esd /index:1


If you have install.wim or boot.wim in your sources folder:
dism /Get-WimInfo /WimFile:F:\x86\sources\install.wim /index:1
or
dism /Get-WimInfo /WimFile:F:\x64\sources\install.wim /index:1

dism /Get-WimInfo /WimFile:F:\x86\sources\boot.wim /index:1
or
dism /Get-WimInfo /WimFile:F:\x64\sources\boot.wim /index:1


For single iso:
dism /Get-WimInfo /WimFile:F:\sources\install.wim /index:1
or
dism /Get-WimInfo /WimFile:F:\sources\boot.wim /index:1