Windows 8.1

How can I put a desktop icon for Google Maps down on my taskbar? I try to drag it from the desktop down to the taskbar, but
it doesn't happen.

You have my deepest sympathies.....
I've been trying to do that same thing, since the first day that I installed Windows 8.1. (it's been a while)

So, not being able to put my favorite internet shortcuts in my task-bar, I put them in a folder on my desktop. I number them according to their importance. Like:
1 Windows 8 Forum
2 Windows 10 Forum
3 Kia Soul Forum

I can also minimize that folder to the task-bar.
I usually leave that folder open all day, but I try to make it as small as possible so it only shows the names and not all the peripheral BS. I actually have two folders, because I work too many forums to fit in just one folder/window.

If memory serves, I've not been able to directly copy an Internet Shortcut to the Task-bar, since Windows XP.

I guess that's one of those "Improvements" that we're suppose to embrace. Eh?

Cheers mate!
TechnoMage