Updating JupiterVersion:

I have JupiterVersion: as my theme for my wordpress website. I resently took over the site maintenance, but did not get a lot of information from the previous person.
How do I upgrade the version?

If the theme has been purchased from your account (This means you have access to that account). You can re-download the theme and update it.

But to be sure, you can consult the documentation of the theme first of all.