Choose the File System drop-down, and then click 'FAT32 (Default).'.Click the Partition Scheme and Target System Type drop-down, and then select 'MBR partition scheme for BIOS or UEFI.'.Click the Device drop-down, and then select the name of the USB storage drive you just formatted.
The Rufus USB Installer is free, open-source software that lets you ultimately take the Ubuntu ISO installer and create the bootable USB Ubuntu installer. Steps to Create a Bootable USB Ubuntu Installer in Windows