1: Monotheism is belief in one god. Jews believe that G-d is a single, unified being (as opposed to Christians that believe in a Trinity.) We do not daven to angels or other heavenly beings.

2: Generally, Orthodox jews daven 3 times a day: Shacharis, (morning) Mincha (afternoon) and Maariv (evening.) We use traditional tefillos said in a set order. Men usually daven in a minyan (congregation of 10 men), women can daven alone if they want. There are other tefilos that can be said outside of the set time, eg. Tehillim (psalms).

3: Tbh I don't think most people care about what people in other religions do. Judaism isn't too concerned with what will happen to the non believers. I remember learning that those that follow the sheva mitzvos bnei Noach will have a share in olam haba but don't remember what would happen to the non believers? I don't think it's discussed very often. As an aside, I don't think Muslims transgress any of the 7 mitzvos, but I don't remember if they would be considered Noahides if they don't believe in those laws.