I can't believe I'm about to do this, because I normally HATE HATE HATE them, but try googling "must have basics for women". I am NOT suggesting you go out and buy the things on that list, because those items may not work for you.
Like, white button up shirt is soooooo not for me, because white washes me out, buttons gap over my bewbs, and the arms are always too tight no matter how much I size up. Black blazer? Great pencil skirt? I do not have a blazer & skirt kind of life, and black is harsh against my pale skin. So I have to think about the function these recommendations serve in a wardrobe. I have a black moto style jacket that serves as a "complete" piece that makes jeans & a tank top look a bit more pulled together. A button up shirt becomes a fairly basic knit top for me, because it can go with lots of things.
So reading those lists can kind of give you an idea of some basic foundational pieces to use as a starting point to build a wardrobe.
Now I'm going to give a suggestion that is useful in a more concrete way. Go to the blog portion of this forum. Angie is pretty freaking amazing at her job as a stylist, and she shares a lot of her knowledge for free in that blog. She watches trends, then she makes posts that interpret those trends for a very wide variety of people regardless of budget, size, shape, aesthetic/style persona. While you're at it, read about style personas here on this site, because giving myself a style persona has helped me shop more effectively. If I'm out shopping, I know to avoid certain types of items because they don't fit the style I want to project. i.e. argyle is very preppy or classic, and I am neither; so no matter how much I love to LOOK at a brightly colored argyle, I shouldn't buy it because it doesn't fit my personal aesthetic.
Final note: don't feel like you have to define your aesthetic right away. Even Angie, with her very well defined aesthetic, has evolving tastes. Experimentation is good, even for people who think they have their style figured out, and I see a lot of that on this forum. So don't feel pressured to define yourself or your aesthetic, we're very ok with uncertainty and evolution here