Consistent dandruff problems. To time.

I've been having this dandruff problem since 2013, I've been using anti-dandruff shampoos but it's not working. I haven't got the chance to go to a specialist due to my busy schedule. It's constantly itchy and the longer my hair grows, the more it becomes irritating. But if I cut it, it goes away (though it still itches). If I let it be, it leaves red patches located at the edge of my hairlines, specifically on my forehead and behind my ears. If I am not able to take a bath for a day, there are dandruff also forming on my eyebrows. When my beard gets long enough, the same happens and as well as the surrounding areas in my nose. But when I take a bath it just disappears or if I put moisturizer. My older brother was diagnosed with psoriasis when he was still a teenager, btw. I've read read things on the internet but really not paying much attention since it disappears from time to time. Thank you for reading, and I hope you can help!