You do not necessarily need to believe in a "soul". However there is no doubt that we consist of something else besides matter and energy. This something else is consciousness.

A complex enough arrangement of matter, like our brain, produces consciousness. This is nothing supernatural, it's just a property of matter. Animals can be conscious also, though on a lower level. Most AI scientists think that even machines can gain consciousness when they are complex enough.

This has nothing to do with the meaning of your life. Either you gave your life a meaning, or you didn't. Obviously, you can be conscious but still have a meaningless life. Then you might need a replacement, like a god, a guru, an ideology etc. that serves not as a meaning, but at least as a purpose for your life.