I use Firefox with strong privacy settings. I use Chrome as backup for the few sites that don't work on Firefox with those settings. I haven't used IE for many years and I've never even seen Edge because I use Windows 7.
I like Firefox because it is flexible. With Chrome you get what you get. However, later versions of Firefox have become less flexible. One example is tabs below the toolbars. Another is the ability to drag shortcuts to the desktop. Because of this I have updates disabled - I only update when I feel like spending half a day to change config settings and policy files. Also, lost my Red Cats - Blue Flavor theme as old style third party themes are no longer supported.
I have Open Office installed but I continue to use Office 2010 because it was paid for long ago and does not depend on the internet.