Upgrading 6.38 to 8.6.1 – but 6.38 db is postgresql

Good day,

I’m a greenhorn technical assistant at a public library and one of the things I need to do someday is get our site off Drupal 6. In order to test the migration, I’ve gotten a virtual machine going with a clean install of 8.6.1. I have all the web files copied over and I have the ability to connect to the Drupal 6 database from this VM.

Unfortunately, this Drupal 6 database isn’t MySQL or a compatible, it’s postgresql. When I go to /upgrade, the UI only presents me with MySQL, MariaDB, etc.. on a greyed-out radio button. When I run it with the correct port and credentials, it eventually says “MySQL server gone”, which makes sense, because the D6 server probably isn’t even running MySQL.

Is there any kind of migration path I can take without having to clone the database in MySQL first? If I do have to do that, any reccomendations for tools?

Drupal version: 

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