Shall I open the door?
Will I open the door?
So far as I know , the first sentence means will you allow me to open the door?
The second question means Will I have the ability to open the door? ( it is not usually)used in the sense of seeking permission)
You shall do it(obligation)
You will do it ( prediction)
I shall do it((intention- formal)
I will do it( intention- more usual or common than I shall do it)
Do native speakers in all the countries follow the distinction between shall and will or does it change from country to country?
I am asking the question because some native speakers say that there is not much difference between will and shall and some say there is clearly a diference?