You can add search variables to the catalog of the database with the parcs.
Like this
https://YOUR-DOMAIN/parcs.html?
searchfield=
country&
search=
germany
All you have to to is to add the value with the county-name to your url
Like this<a href="https://YOUR-DOMAIN/parcs.html?searchfield=country&search={joodb field|country}">{joodb field|country}</a>
It seems to me that you do not need the second table.
Normally you don't write the complete Value of the connected table.
You just have a number (id) of the related field in the second table.
Parks.id_country => Countries.id :: Countries.name