To dream of flour represents feelings about actions taken to make a situation work. How much or how little of something you need to do in order to make a situation or solution feel good functioning. Only enough effort to solve a problem and nothing more.
Negatively, flour in a dream may reflect your feelings about how far you need to take a lie to make people feel good believing you and accepting it. How far you need to use dishonesty to make people feel good complying with you. Only doing what you feel you have to do in order to get what you want with no genuine wish to help others. Doing only what is required of you to keep people happy and nothing more.
To dream of using flour on a fire may reflect an attempt to handle a crisis with just enough effort to fix it and keep people happy. Not wishing to be 100% helpful or honest in order to stop a problem from getting out of control and doing only what helps you stay comfortable avoiding blame or extra work. Contributing only enough to keep people from bothering you.