Hi,
I have few questions on option selling, requesting you to have a look.
Let’s say, I am selling 1 lot of bank nifty @26800CE . Price for option is around Rupees 200.
Here are my questions.

What are the formulae to calculate required span and exposure margins to calculate total margin (Rupees 53,095) as provided in image above?

How to calculate profit and loss? With respect to price of asset or price of option premium of that asset?

How to calculate profit and loss with respect to price of asset?

a) Let’s say price of bank nifty moved to 26850. How to calculate loss at this price?
b) Let’s say price of bank nifty moved to 26750. How to calculate profit at this price? 
How to calculate profit and loss with respect to price of option premium of that asset?

a) let’s say price of option while selling is Rupees 200 and it moved to 250. How to calculate loss in this case?

b) let’s say price of option while selling is Rupees 200 and it moved to 150. How to calculate profit in this case?

Above what price of asset I need to add additional funds to continue selling the option?
As a newbie here, I am totally confused.
I would be grateful to you if you could possibly help me with to clarify these concepts.