Have you considered the fact that the Finder window has preferences like everything else on your Mac? It does, and setting them can make your life easier.
While in the Finder window (click anywhere in the empty space on your desktop so that Finder appears in the menu bar next to the Apple icon), select Finder > Preferences. As you can see from the following image there are four that you can set.
This is one of my favorite because it lets me determine what appears in the side bar when I open a finder window.
The Advanced tab is also worthy of your interest.
In this one you can make sure that file extensions are identified. If you don’t like being warned before your trash is emptied, here is where you can turn that warning off.
Take a minute or two to check these preferences out.