Hello please help I'm a single mum who's loseing.

Hello please help I'm a single mum who's loseing the plot with my car so many things keep falling apart with mazda but despite the electric window switch comeing off in my hand that now doesn't work at all now this more serious problem has accurd being the heater control switch on dash just fell off not snaped but I can't seem to get in the thin long slot to re attach the movement button please can u tell me how I can do this myself as weather gettn worse and can't get screen to demist before driveing I need to drive my car I have a little girl but I can't see out windscreen properly I'll be greatfull if you can help me I have nobody else, claire