Will is used:
-for a future tense. Eg You'll be nineteen years old next week.
-to indicate a will. Eg I will survive!
Shall is used:
-to make a sugestion (with 'I' or 'we'). Eg Shall I close this door?
-as an old-fashioned modal instead of 'will' (with I or 'we'). Eg I shall never forget how clever you are
-to say something certainly will or must happen. Eg We shall be there to meet the train
That list is not exhaustive.
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Student or Learner