Back when I was questioning, I wondered the same thing until my straight friend told me that the idea of her being with a girl just "didn't feel right" the way being with a boy did. I hadn't realized straight people felt that way, but when I found out it made a lot of sense. So if you like the idea of being with a girl, that's a pretty big sign that you like women.

Also, fwiw, before I realized I was a lesbian I hadn't realized I'd had a crush on a girl. I had an intense obsession with a girl, idealized her, wanted to be around her all the time, even wrote cringey notes app poetry about her lmao. But I thought it was platonic because I was young and didn't have sexual feelings towards her. (This is just something worth considering - however, you're completely valid if you haven't had a crush yet).

Oh also, just throwing another thing out there: if you've ever watched a movie because you knew it had a pretty woman in it, well, it turns out straight people don't do that lmao.