What you are referring to is called 'greeking' and is typically done with lorem ipsum, which is a fake latin-looking gibberish.
So one option to use your preferred typeface, but lorem ipsum as your content.
Another option that I often use is 'xxxxxxx' text. This isn't nearly as pretty, but it's blatantly obvious that it's not real text. So something like: Xxxxxx xxxx xxxxxxx xxxxx xxx xx xxxxxx x xxxx.
The advantage is there is no mistaking that for real text. I've seen cases where Lorem Ipsum accidentally made it into production.
But to answer your specific question, there are actual fonts for this as well:
Blokkfont uses a style that is reminiscent of the marker comp days where to show blocks of text, you'd simply use solid lines (drawn with your marker).
Lettererror has a few options that emulate sketchy scribbles.
And there are others. Google 'greeking font'.