I would be pleased to answer your question .
From you history I am pretty pleased to know that you have realistic expectations. That is a very important part of your treatment.
based serums available over the counter are good for individuals with a tanned skin and sensitive skin.
The Vitamin C serum available nowadays come with new technologies which are not irritant and have added advantage of lightening the skin .
Avoid Bleach and Chemical peels
on your skin .
It might take some time for the treatment to work . You need to book an appointment with the Dermatologist
ans discuss the above.
Thanks and Take care