Now there is only single win8 OS on my laptop. How I create usb with ubuntu installer, but after reboot win 8 with sytem repair and nothing ubout ubuntu installation. I have cheked BIOS settings: usb is first. PS I want to repalce win 8 by ubuntu
2 Answers
Download Unetbootin for windows and then from Unetbootin select the Ubuntu ISO image as per image
Select the Diskimage option , then Browse to the location of the Ubuntu ISO image from the .... button.
IMPORTANT option , select the Type and Drive Option Very Carefully to avoid data loss . If it is Usb Drive , most probably will be sdbX , sdcX, do a cross check and Proceed with OK option.
Until you create a Live Bootable USB Disk from above method , USB Drive cannot boot .
If you want to replace your Windows 8 installation do follow this Answered question here as
As you said , if you want to replace Windows , then from this illustrated answer at this option

Select the second Option as Replace windows with Ubuntu.
The problem was the flash drive. With CD everything was installed properly. The appearance of the error windows at the same time as trying to install Ubuntu made me very confused.
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