Just a heads up that this topic makes some people feel really uncomfortable to think about.
It's because I don't think the "self" exists either. Without a self there's nothing that even could make decisions to begin with. I don't believe in some "entity" or a "soul" somewhere inside our heads, behind our faces, looking out into the world and making independent decisions. We're not authoring our thoughts and actions. They're just appearing. You don't know what you're going to think next, and you can't think of a thought before you think it. You can even observe this happening in real time by just paying close enought attention.
We're biological beings that consist of matter, and matter obeys the laws of physics. "Free will" as in "I could've done otherwise" doesn't make any logical sense to me. If we could go back in time we'd all do the same things all over again. That's how deterministic universe works. The key factor here is consciousness. It feels like something to be. The sense of free will is probably useful belief for survival, but for the very least I'd argue that it's not like most people think it is.