Windows 7 will not install via a USB 3.0 port natively. In the past, there have been various solutions. Most old laptops had a mixture of 2.0 and 3.0 ports, so you just had to use a 2.0 port. You have also generally been able to go into the BIOS and change the USB 3.0 settings to either “legacy support” or “auto”. Unfortunately, there isn’t a setting in the new Lenovo laptops that you can change which allows for a 3.0 port to be seen as a 2.0 port for installation purposes.
I found an Intel utility that adds a 3.0 driver to your Windows USB installation media which worked great.