Need help with Nergigante So I’ve been stuck on Nergigante for a few days now and I need help.

I’ve been using all of the defender armor and long sword (something I’m not proud of) I have been my longsword at level six or seven and the farthest I get is it’s nest before I choke, what can I do to take less damage. Should I be playing multiplayer against it and if so does any here want to join?

Anything Helps!