[anilin]

I am not sure which NH2 group in this compound would be first protonated and deprotonated in the presence of a strong acid and a strong base respectively. Is it the NH2 attached to the sulfonate group that will be first deprotonated with a base(i.e. more acidic)? because S&O are electronegative and also forming resonance.?

[orgopete]

That would be my guess as well. Deprotonation of the aniline would require resonance stabilization through the aromatic ring by the sulfonyl group. That effect should be diminished compared to the attached NH2 group.

Protonation should be the reverse.