Hi Wu, Although I am not very good at analyzing poetry, my best guess would be he meant something like what you said in your first guess. He was alive during the freedom strugle of India, and also wrote the national anthem. I think context plays an important role as well, so I think he is encouraging people to join the freedom fight, and asking them to sacrifice their lives for a greater good.

Has no obvious meaning in English. "giving it" has no obvious meaning.