What is it that you don't like about yourself?
Give us example pics of the type of cute you like
The best advice I can give to be cute (at least concerning outer appearance) is to eat healthy, wear lots of sunscreen, get enough sleep/water, and find a skincare routine that works for you!
For cute clothing I suggest starting out by shopping second hand
Really great secondhand app, it's like eBay but the format feels like instagram
My favorite rags to check on there are, jfashion, swankiss, liz lisa, ank rouge, btssb, lolitafashion, angelic pretty, my melody
Although I have an account there I haven't bought anything yet! But also like ebay but filled with cute second hand lolita clothing and items! Market kei has other jfashion if lolita is not really your thing
This is where I first started shopping and where you can if you're on a budget
Good for starting out a wardrobe and seeing what you like vs what you don't
Always read store/item reviews and remeber that these items ship from china so it takes a while to get here (is Chinese New Year still going on? I wouldn't reccomend shopping during Chinese New Years)
Favorite shops on ali, meowgirl, LoliGals Lolita Store, Shop1247996 Store, and himifashion also keep in mind its a hit and miss when shopping on aliexpress most people just buy bags, shoes and accessories
And remember that you can't be a cutesy anime girl,(a lot of girls in the j-fashion scene try to make it seem like they are but it's either, photoshop/filters, makeup/circle lenses, or maybe they are cute and got lucky with genetics!) but you Should aim to be the cutest version of yourself that you can be! Good luck!