I have a damaged sculp and hair help me I need help getting my natural hair back

So... ever since ive done a failed keratin treatment. It was not real keratin it was cheap and it did not help me straighten my hair at all. My hair has always been kind of dry and curly because of my genes, but straight hair fits my face more so ive been blow drying it in a wrong way without even knowing what I was doing just to give it some volume, it didnt look straight after the blow drying process btw but yeah I didnt care at the time as it gave me the volume I needed. I used to take a shower put on some shampoo dry it 70% with a towel and then I would just blow dry it. It went on for like 3 months and then my hair got really....REALLY damaged. It was absolutely broken and looked terrificly bad. I would then just go on and do another straightening process that worked just perfectly but there was just one problem about it. I found it extremely difficult to have the volume and apply the hairstlye that I wanted because everytime I would wash my hair it would just fall and it would be so wet and hard to style. So yeah I went on to do the most stupid thing ever, I didnt wash my hair for a month. Not even a drop of water, it didnt look that bad it looked just really greasy and uncomfortable but I no one really noticed and I didnt mind it, my sculp was absolutely broken. I had the worst hair ever. So yeah I went on and washed it, completely dry again with damaged hair and my sculp was ruined. I searched for advice everywhere on what to do and I couldnt find any help so I did that straightning treatment once again(not keratin by the way its another protein). And I left it for another month, sane results, greasy as hell, but yeah moving on.
Now I was really sick and tired of that greasyness so I decided to just blow dry my hair every like 3 days and not wash it except like every week, and my hair is just completely damaged. The area I live in is horrible everyone is just born with their perfect genes and straight hair and I am just there like, what should I do... all they do is just shampoo their hair put on some conditioner and oil and serum and thats it. Its about time I just found out about clays and pomades and waxes etc a few days ago. And I do not know anything about them. Please I am legit dying HELP ME. I just need some tips on what to do to heal my scalp and in the same time I want to look good so I need some tips on how to get straightened hair and look good outside. I currently have damaged hair and a damaged sculp from all the blow drying and the MONTHS I spent without washing my hair. I need to know what oils and products/prestylers to use before blowdrying with round brushs. ANY help is appreciated I need my hair back. Thanks