It is also not clear to me how I would even upload a folder into my blog - where is this feature located?
Please see this thread: http://support.pressharbor.com/discuss/topic/13?replies=1 to learn about how to ftp files and folders. You can find all of our FTP-related support docs at http://support.pressharbor.com/?s=ftp and forum posts at http://support.pressharbor.com/discuss/tags/ftp .
I am also a little confused as to why content is not editable - apparently in other WordPress formats one is able to change their "permissions" in order to edit content in their header
Yes, and in many others it is not possible to edit files via the control panel. The technical answer is "it depends on whether Apache runs as the user who owns the files or if it runs as a different user such as apache." Managing your Wordpress works differently from server to server, web servers vary widely, and what is safe or workable on one server is not safe or workable on another.
In Blogharbor there was a feature under security (in the general category) which allowed the user to add additional header information. Why can't that be available on Press Harbor?
Because it does not exist in Wordpress. We did not write Wordpress, we can only install it for you and manage its upgrades. Please take it up with their developers if you wish to see a feature added to it.
If you could direct me to clear, simple, step by step directions which explain ftp and how to do everything you wrote above, it would be helpful.
We have a number of places for you to learn about http://FTP. See our first reply above.