Lived with this issue, but do I have to? Small window

Hello,

I've never been able to fix this, if it's fixable. No matter how many times I create a large window default size for my main hard drive, when I attempt to drag an image or file on to it, to place it in a folder on the hard drive, only a truncated window in the upper right corner of the screen opens. I'm forced to manipulate the file/image to scroll down/up slowly to the folder I need to place it into. I'm trying to permanently make the Macintosh HD open as a large window so I don't have to scroll anywhere. In my case, my main hard drive is named Macintosh HD. Below is what it looks like when I try to drag a file onto main hard drive. There are, at least 35 folders on that hard drive. Only a few are visible. Thanks for any help.