I'm currently on 48kg I want to gain another 10-11kg what can I do and eat and maintain that weight
If you have access to a gym feel free to use my workout plans. As for gaining due to your light weight I recommend looking at clean bulking plans.
You should be able to find a basic meal plan on the internet (try bodybuilding.com)
You might have to adapt it to your lifestyle though so remember to factor in things like food cost.