Hello,
It seems that the word navigation by holding Ctrl and pressing arrow keys does not work anymore on Windows.
The feature I am talking about is very basic, so I think it must have been there - I use it a lot, even in the browser when writing this post, and only noticed it’s not working in Obsidian recently.
It works when you hold Shift key and select the words, but it’s not the same.
Just to check, because I also use it frequently: It works on Linux Mint 20.1/Cinnamon with Obsidian 0.11.13 (installer 0.10.11).
Try with all plugins, themes, CSS disabled. If it then works, enable one-by-one to find the cause. Be also sure that you haven’t accidentally used Ctrl+arrows as hotkeys.