No.
The container only contains the necessary code to run HA. You will never modify the contents of the container. And even if you did it would get wiped out on the next update of the HA container image.
You will simply go to the base OS (Linux in your case) and install SSH and Nodered there.
But…
I would learn more about containers if that is the way you are wanting to go. I use Docker for almost everything on my system. It’s not too hard to learn.
And then I would install Nodered in another container instead of directly on the OS. (you would still install SSH directly on the OS tho).
Or if you really don’t want to learn Docker then just either install HA Supervised (but you will still likely need to figure out Docker at some point even then) or use HA OS.
Either of those two options hide most (HA Supervised) if not all (HA OS) of the backend operating system from the user.
HA OS really limits your access to the OS tho. So if you plan on running others things outside of the HA ecosystem then go with Supervised. Or better yet, lean Docker and stay with HA Container like you have now.