Islam is not only that, it's a religion and also a way of life that gives in your hand laws that specify the way humans should behave with each other under it's rule, you asked about people under islam that don't want to converts this is possible in Islam but they have to pay an annual tax (like muslims) but in the other hand they get protected if there's a war and they don't have to take part in the army and they are treated equally as muslims in the legal system.
I just know few informations about islam, but i don't spread lies.