Hair dryness can be due to pollution, other environmental factors and also nutrtional deficiencies. Hair gets damaged after parlour procedures. So kindky avoid all those.  Use conditioner regularly and leave on serums for hair. For lice,use perlice 1%rinse. Apply to entire hair, leave for 10min and wash and repeat after 1 week.  Dead Nits to be removed mechanically by nit removal coomb or apply vinegar and coomb your hair. There are plenty of causes for dark circles. It could be hereditary,  stress, venous congestion, lack of sleep, pigmentary denarcation line,  tear trough deformity, repeated rubbing the eyes, cosmetics, anemia and other nutritional deficiencies. So we have to determine the cause and treat.  You can use avarta under eye gel and sunscreen.