how to help my solo kitten release her energy (without attacking my feet)?

hello all! as a bit of background, my childhood cat passed away a few months ago at the age of 19. most of her care had fallen into my hands so after she passed it wasn’t long before i adopted another cat- from the same shelter, actually! i adopted her at 6 months old, already fixed, and she’s coming up on 8 months old later this month.

she’s the sweetest thing and the moment i met her she absolutely melted in my arms. she purrs so loudly and LOVES attention. i was concerned about her being an only-kitten, but she was never super interactive with the other cats at the shelter and she’s very good at keeping herself entertained with her toys.

however there’s one issue: the attacking of feet.

she does this in multiple ways: one, for affection. when rubbing on our legs doesn’t get us to pick her up and pet her, or if we walk away while she’s doing so, she’ll attack. she’s very intelligent and very communicative and is learning new words every day, so i’m thinking about getting some of those word buttons to help her communicate better?

two, she does this when she seems to have so much energy she just doesn’t know what to do with it. this is when the claws come out and sometimes she’ll bite. i know that this is a consequence of her not having a playmate. she’s very happy and i do my best to play with her as much as i can, but this is one area that i’m stumped.

i will say that getting a second cat is absolutely not in the cards right now. one day maybe, but as of now i just can’t financially swing it and still keep up with food/vet/flea meds/etc.

so my question is: does anyone have any ideas as to how i can help her get this energy out in a better way? i’ve been discouraging the behavior but have nothing to redirect her towards, so it doesn’t seem to be changing.

also: when does this kitten energy start to wane? like i said the only other cat i’ve ever cared for was already 15 or so before i started taking over her care. i knew a kitten would be different but i’m still a bit overwhelmed by the amount of energy kittens can have lmao

any insight is appreciated!! thank you!!

TLDR: my 7.5 month old kitten (already spayed) is attacking my feet a lot and while i know getting a second cat would help, it’s not something i can do right now. any ideas how i can redirect her energy? when does this kitten energy start to wane?