Are "recruiters" on LinkedIn scammers?

For some context: I'm mid career change. I was not in tech at all, and I recently graduated from a bootcamp for SE. Point is, I doubt my linked-in is crazy attractive from a software engineering perspective. That said, I get messages from "recruiters" on LinkedIn constantly. I've never been huge into linkedin, as my old career I had for a solid 10 years and never needed it, but these feel scammy to me? However, it's also super difficult landing this first software engineering position, and I wouldn't mind going through a third party like that if they're at least somewhat legit.

Has anyone here had this experience and/ or used any of these "recruiters"? Are they all scams, or are some legit? Or maybe, are they mostly legit but with some sort of catch where they take a big cut or something? Anyone's experience or insight would be appreciated!