Deperately Need Advice

I have had a dry scalp problem for many years and have tried many things to no avail. My hair is long-ish and is generally frizzy all the time. In the past I have used coconut oil, jojoba oil, tea tree oil, acv, baking soda. Recently I have been using argan oil twice daily (morning and night) to moisturize my hair but I would often see flakes regardless. Generally I would wake up, wash my hair with water and apply the oil, comb my hair and repeat the process at night, flakes keep coming back.
I read about the no poo method and I was hesitant to try it given the frizzy/dry nature of my hair (leaving it as is and not applying any type of oil/moisturizer). It has been a long and discouraging journey and I am at the point of almost giving up. So my questions are, how often should I actually wash my hair? should I stick to water only or baking soda+acv? If I use argan oil to moisturize would that still count as no poo? Are there any other things I would need to know?