For some reason, Microsoft made it harder to track down Device Manager in Windows 10. Fortunately, you don't need to hunt through a bunch of menus to find it — Microsoft was nice enough to add other ways to access everyone's favourite (and former) Control Panel item.
The easiest way comes via Microsoft's own support site. I guess the company realised people were confused enough to justify a write-up:
Press and hold (or right-click) the Start button, then select Device Manager from the context menu.
However, as Martin Brinkmann over at gHacks points out, there are a couple more shortcuts. Hit Windows key + R to bring up the Run dialog, type "devmgmt.msc" and hit Enter, or type "Device Manager" into the Start Menu's search box.
Sure, Device Manager isn't something you use often, but when you do need it, it's nice not having to jump through a lot of hoops to access it.