Welcome Rich!
This is definitely a melodeon ( but there are many different kinds of melodeon).
The "accordion", as distinct from a melodeon, is another animal entirely
Some people own and play both, but they operate very differently and cover different musical genres, although there is some overlap.
Playing one won't enable you to immediately play the other.
Generally, you'll need to decide which one you want to go for, as both will require considerable study.
Even then, each type of instrument is part of a whole group of broadly similar instruments comprising a whole family: i.e. there is a family of melodeon -like instruments and another (separate) family of accordion-like instruments,
Which particular instrument you choose would depend mainly on the kind of music you want to play and reference groups you want to identify with.
So, check out with your reference group what instrument/s they are using before buying anything at all!
Rather than making the trip to see this particular melodeon, I'd enquire around your nearby "pubs"* to see if any of them are hosting Irish/Celtic music nights and turn up to those to see what goes on and talk to the "musos" about their instruments and ask to try them.
Here's a one row melodeon in action:
An Irish example:
*An Australian pub or hotel is a public house or pub for short, in Australia, and is
an establishment licensed to serve alcoholic drinks for consumption on the premises. They may also provide other services, such as entertainment, meals and basic accommodation.