Hello, Free Mode unlocks after finishing the intro chapters (after Black tamer's barn training quest). Free mode will be available on title screen after it is unlocked.
For faster progression i recommend checking the (above) main post "Walkthru Videos" first and 4'th video, as they show how to complete these intro chapter quests.
Another option (not recommended) : you can download the completed game saves from the Saves and Guides channel on Discord server (link to the discord server can be found in the main post above).
If you're encountering any issues, feel free to contact me (here in comments, discord or via email).
Cheers,
~NK