Primrose "Fourteen" Bellamy would always find something to do for her own free time.
She usually spends her time
journaling her thoughts and sending a copy of them to her unknown friends and family outside of Karakura (as if she had a pen pal consisting of a friend + family group of 109 girlies) so they too get to learn what "Fourteen" has experienced.
In addition, she started getting herself into
learning electric guitar just so she can learn to play this one song that she loves listening to as a "workout song for robots"
Recently, "Fourteen" also
got herself a gaming console to kill time... though it has made her very distracted and a little
too "in the zone" with how she balances video games with actual responsibilities. You might even find her getting entranced playing a game
based after another Polyphonia project/story, like a twin-stick shoot-em-up type game for furries of rave culture (similarly to the game below by gameplay).
The console may be modeled after a GameBoy Pocket in-game but I'd rather pretend that it's something like a Steam Deck or a
Retroid Pocket Nova handheld system, mainly for the reasons of retro game aesthetics (as opposed to using a Switch model in-game, which is a very modern gaming system).
Still though, whether it'd be her playing electric guitar, distracting herself with video games, journaling, or just looking around and trying to meet people, every day feels like a new day for her with something to do!