Free will is an illusion. Every decision we make is based on what we want in that moment, but since we can't choose what we want, we therefore cannot have free will.

Say I had to choose between cereal and oatmeal for breakfast. I could eat the cereal, because it tastes better, in which case my decision was dictated by my desire for something tasty. If I was to choose oatmeal, because it's healthier, in that scenario my decision was dictated by my desire for something healthy. But I cannot choose what I desire. Just try to change your desires. Think about something you want, and try to unwant it. You can't do it, so therefore you can't make conscious decisions. Free will doesn't exist.