My Toshiba laptop goes to Windows 10 login directly even after I set the first boot device to USB in BIOS. It is a Windows 10 install disk.
It seems that this Windows 10 install disk is not valid for you or check if there is anything worng with this Windows 10 install disk,then fix it.
You may do better asking at https://www.tenforums.com/
Is your USB Stick recognized in Windows when you plug it into your Laptop?
In my BIOS, I am able to select what Hard drive or USB Drive to boot up on. Do you have something similar?
Is your USB Stick made to boot up by using software similar to Rufus or Windows 7 USB/DVD Burner or is this a USB Windows installation drive that came from the manufacturer with Windows Installation already installed?
Test your USB in another computer to see if it is recognized and boots up from it. If it doesn't then the problem is with the way the USB had Windows Installation files burnt into it.
I had something similar happen to me in the respect my wife's computer wouldn't recognize the USB stick nor DVD. Turned out that I needed to make the DVD boot-able which I didn't when I burnt it. I just copied the Windows Installation files to the DVD. Afterwards, when I made BIOS to check first the DVD drive it detected my DVD Disc and booted up.
The USB can be seen by Windows. The problem is fixed coz the burning process was not done completely. Re-burn it and it worked now.