I think he means:
- goto history.google.com (now at https://myactivity.google.com/myactivity)
- up near top center click "Filter by date & product"
- in the list of check boxes, enabling individual boxes takes you to pages that are identified by the URL appendage "product=1,"
- where, for example, product=1 is when you have enabled Android in the "Filter by Google product" list.
Most people would just select a checkbox, not edit the URL Product parameter, but it can be done both ways.
If you do not have an Android device, the 'product=1' link may not work for you.
All this does not get you to your wished for "device," because 'product' means 'app,' not device.
I too want to see Chrome history for all my devices, whether that device is signed in or not. I used to be able to do this via +h, but then Chrome de-featured and just showed me 'logged in devices,' and now since a subsequent de-featuring, that no longer includes my Android device. I can see my Android history via the above steps, but what a PITA. I still have no way to see PC #1's history while I am using my PC #2 if my PC #1 is in sleep-mode. While PC #1's history may be in https://myactivity.google.com/myactivity under the Chrome filter (URL tail is "'product=6"), I cannot obtain any device info the history as displayed in MyActivity. FML. and FG2.