Mr. lybrate-user ji
it's great that you are healthy and keeping fit.
Sir, it's good that you are concerned about your health and planning to improve your immunity to be safe from covid-19. Please remember that immunity plays important role but still more important is to follow guidelines.
Maintain physical distancing, use mask, wash your hands frequently and makes sure that you take at least 5 litres of clean drinking water and balanced diet.
For more please free to communicate audio/video after appointment. Thanks and regards.