Karen, to run your own linux server, it's simply a matter of signing up
for the free core live patches konocal provides to keep the core os up to
date.
To keep the system itself updated, every time a person
logs into their shell account, the system will let you know how many
packages need updated, then you run two commands, sudo apt-get update, and
sudo apt-get upgrade. That's pretty much all there is to it.
If your organization has the funds, linode even has a service where for
100 bucks a month (I think it's a month, could be a year, but I think it's
monthly), they'll even apply the updates for you so your organization
doesn't even have to do that.
I'm sure that there's someone at your organization that can run a couple
commands once a week or so to keep programs up to date.
Running a server isn't like it used to be back in the 90s when I first
started self hosting linux machines, and had to do all the maintenance
myself, hosting has come a long way since then.
If your organization truly has nobody that is tech savy, you could easily
get someone to do the initial setup for you, (though I believe linode will
do that too for a fee), then you won't have to do anything but get someone
to watch the logs to make sure nothing is broken, though honestly, even
that isn't truly necessary since anything that is truly broken should be
noticed by the server monitoring and patched on the fly. It's always a
good idea to have someone watch the logs though, just because it's always
good to know what's going on with the system as a whole, but you don't
have to be a tech specialist to do that task, just a bit knowledgeable
about what should be running on the system, and what isn't supposed to be
happening, that's pretty much it.