Thanks for writing in.
You can apply Glyco A lotion over the darker areas at night.
Use a good quality sunscreen in day time every 3 hourly starting at 9 in morning.
SPF of 50 for face is good enough. Photoprotection is a must for any pigmentation problem.
Take a lot of lemon juice daily.Also you can take vitamin C
You can use Safi also.
Oily skin can be treated with some medications .They are prescription meds and have to be taken under doctors supervision.
I encourage you to visit a qualified dermatologist
for proper diagnosis and treatment.
Hope this helps.