Hi,
Welcome to health care magic,
Firstly I have read your query and understand your concerns as you are losing hairs and 
dandruff.
Your Hair problems could be due to poor nutrition (hair loss) and 
fungal infection (itchy 
scalp which could be dandruff).
You need to take antifungal shampoo treatment (such as 
Ketoconazole) for fungal infection which may require longer time.
Hair loss can be regained by 
MINOXIDIL lotion application on bald areas.
Minoxidil should be used on absolutely clean scalp. Since the drug is available in an alcoholic base therefore it won't mix with Oil and Oil would form film impermeable to Minoxidil.
You may use oil 2 hours before shampooing hair.
Results are usually noticeable over a period of 6-12 months of regular Minoxidil topical use and oral treatment.
However you should take minoxidil only after consulting skin specialist as it is a prescription based drug.
Hope this detailed information will help you.
Regards,