Our family pet cat is very well-behaved, but she's rather plain. She doesn't do any of the crazyfun things cats do on the internet. Is there a way to bring out her playful side?
Remember that videos become popular on the internet because they are exceptional. Also remember that young cats tend to be more energetic than adults, and that cat personalities differ just as human personalities differ.
Having said that, it's a matter of finding something that particular cat is interested in doing. One of mine loves chasing a laser pointer, especially on the couch where she can hurl herself at it with full force and just bounce if she lands badly. The other decided some years ago that the red dot wasn't an interesting game, but absolutely loves chasing a string. One will bound up the cat tree any time I'm going in that direction to meet me eye-to-eye; the other prefers climbing to the top of the 8' tree to supervise his kingdom. One likes to rest on the catnip pillow, the other likes to rest with a window view. One of them periodically tries to teach me to play fetch. One is much better at solving treat puzzles than the other. And so on.
You can also train a cat to play some games. Or the cat may train you. I mentioned that Hazel sometimes wants me to throw a toy so she can chase it; Harry likes to sit behind me while I'm washing up in the morning and try to grab my hand -- I don't know whether he has figured out yet that I can see him in the mirror and am teasing him deliberately. A past cat used to like to hide and grab my ankle as I walked by; unfortunately other family members objected so she stopped that game.
Most of the time, given the opportunity, what they really want is just to curl up on my lap for a warm nap with cuddles.
Give your cat choices, have patience, accept that she is who she is and that most adult cats aren't clowns most of the time, and when she does something you think is cute encourage her. (For pets, just as for children, "cute" is a survival skill.)