With dual-booting Linux and Windows, the Windows boot loader is not used - you use the Linux boot loader (unless you choose the WUBI installation. Most modern Linux distros can use UEFI, and some can even use Safe Boot. Turn off Safe Boot in the BIOS and install Linux. Linux's boot loader will be used and will give you the option to boot Windows or Linux.
I just received my new XPS 15, and am (cautiously) setting it up as a data science workhorse. Windows 10 will be my primary O/S, but I also want Linux. There are so many forum discussions that I don't know what direction to follow.  It seems that a dual-boot setup risks wiping the Dell O/S recovery sectors during disk partitioning.  So, it might be safer to just run Linux from a flash drive (or even run cygwin). On the other hand, it seems crazy not to partition a 1 TB drive, anyway. (On my bespoke desktop I have separate partitions for O/S, programs, and data.)  So, I need to find out how to partition safely -- whether or not I put Linux on one. Are there standard procedures or guidelines from Dell on partitioning and setting up Linux in a dual-boot environment?  Thanks!
How to safely partition a Windows 10 XPS 15 9550 and add Linux ?