Q: how can i view my harddrive and what it contains

One way is to click on the Apple logo in the upper left corner, then click About This Mac > Storage (on the top row).

Another thing you might do is click Finder, then do File > Find from Finder's menu.  Where you see "Kind", replace it with "File Size" from the dropdown menu.  Then choose "is greater than" to its right, then some number like, say 500 ... MB.

OK.  If my second post doesn't help (it should!), also see this article:

OS X: What is "other" space in About This Mac? - Apple Support

Download from the Internet OmniDiskSweeper and Grand Perspective (both free) and open them. They will show all of your files and the respective sizes.

https://www.omnigroup.com/more

http://grandperspectiv.sourceforge.net/

Ciao.