How to install Windows 10 on MacBook Pro 2011 running High Sierra?

Install Windows 10 on your Mac with Boot Camp Assistant - Apple Support

it's too old to be officially supported

so only way to do it I know of is to install windows 7 and then upgrade from within windows,

it not being officially supported there may not working drivers for win10 for everything

if it was me and I could just make do installing windows 10 in a virtual machine like virtualbox or parallels or the likes then I would go down that path