@nanajan26, I'm glad your appointment has been set up.
In your parent's day lung cancer used to be broken down into just a few different types. Fortunately, there many different types have been discovered now. Your EGFR lung cancer is even broken down into different variants. The cellular make up of each variant can determine how well the cancer may respond to different treatments.
That's a long way of saying, I'm not sure what your doctor will have for you. I'm hopeful that they can provide more info and be able to present you with at least a couple of options with pros and cons of each. Please keep me/us posted.