Depends on canon and the -box being written.
There is of course the joke that Fluffies can kill/hurt themselves with anything. Even just the idea of some toys.
There is the realistic animal approach where whatever is fine for cats or small dogs is fine for them.
The toy parody approach where they need official accessories or functional knockoffs. With additional things for experimental play, like finding out the pegs for Transformer modular guns hold Barbie accessories from a certain decade or He-man being compatible with Kenner Star Wars lines.
The general idea seems to be their programming that boosts their intelligence, to varying degrees of free will or faultiness, makes them prefer some things from birth plus the culture of the humans who buy/raise them recommending and manufacturing certain things. Factor in the idea that certain substances irritate them or common versions for human children are too heavy or big/small, plus people being dumb and going for branding, and you just have people paying a lot for Fluffy versions of basic things. Add in idiot humans+Fluffies or Abuse stories making things worse, so Fluffies get splinters on human stacking blocks. Or Hugbox where the Fluffy given dice to play with can learn math.
Ultimately, it works to suit your story.
I prefer realistic animals+toy parody, so I use breeds and “all of the above” approaches. Some like koalas cannot recognize anything except branded Hasbio merch and have no free will as just flesh Furbys who can suffer, some being 5 year old humans in the body of a horse-shaped bulldog that have little flashes of instructions or insight in their mind sometimes that they can ignore or follow.
For writing the young ones as well as educated Hugbox plus realistic takes on mills that are not just unprofitable industrial abuse I advise watching Kitten Lady on Youtube. She’s the primary online source for learning foster care of small animals, and pioneered new ways to care for previously untreatable conditions like Swimmers Syndrome. Very good info, entertaining, and she gets money for real life good works. Chirpies are universally just baby animals.
Otherwise, browse the toy aisle at your local toy or large department store. Take notes and/or pictures. If you are uncomfortable, try downloading a recent toy catalog and watching online guides and reviews. Talkies are treated like a mix of Chirpy and toddler depending on writer.
Some writers have a midpoint between Talkie and sexually mature adult. Emphasis there on human toys or Fluffy versions of them, with an emphasis on roleplay.
Adults with a teen step seem to want interactive toys. Adults skipping from Talkie to adult either need physically stimulating toys or will just play with balls and blocks their entire life. Sometimes the toy is more for the entertainment of the human, sometimes its default programming. Some learn some basic language or engineering nests from blocks, others just stack three high and throw fits when it falls at four.
If you need help deciding, just ask yourself this: are they people with reduced maximum intelligence, animals with AI toy programming, or flesh tamagotchis that are designed to do the same routines and die so you buy more?