Best way to play as low level in the city full of enemy?

i just started to play ingress. In my town, there are 14 portals and 12 are maintained by Enlightened. I am Resistance and there is no way to fight against them, I was trying to destroy resonators, but with no luck. Resistance is here at a disadvantage.

What is best way to get portals, destroy resonators of level 3 and more, when I am level 1 or 2? Do I have any chance? What is the best strategy?