Advisor said pick my own topic. 3 weeks of reading later I'm more lost

First year STEM PhD here. My advisor's approach is basically “go find your own direction,” which sounded great until I actually had to do it.

I've spent the last few weeks reading papers in my general area. I can understand the methods and summarize what each paper contributes, but the second I try to zoom out and ask what's actually missing, my brain just goes blank. I've read 40-something papers and somehow feel less sure than when I started.

So far I've tried citation chaining, review papers, talking to senior PhDs, and messing around with a few AI research tools. I tried mira ai science on a batch of abstracts too, mostly to see if it would surface connections I hadn't noticed. It did point out a couple interesting threads, but I'm definitely not treating any of that as ground truth.

The advice I keep getting is that you eventually “develop a feel for the field,” which is probably true but not especially helpful when you're starting from zero. Does this actually click at some point? How did you find your topic?