Ok, so I have reached Bevelle and first I need to beat Evrae and then I go down in Bevelle self. I can beat Evrae with ease. But then the Bevelle part is very hard for me. I always get slaughtered by those persons. Well the soldiers with guns and flamethrowers aren't that bad, but I just hate that big kicking robot. He kills my party. How can I get past the soldiers and the big kicking robot?

This is my first time trough FFX, so please don't put any SPOILERS here. Or at least not to big ones.