Explain the physical progression of stage 4 metastasis lung cancer in brains and pelvic with an 8 month diagnosis?

Much. This is much too difficult to handle in an email. This should be discussed with your primary care physician/aprn and/or the oncologist. www.thepmc.org.
Not good. There is no treatment that really helps in the long run. There is some local treatment, particularly for the brain metastases. Essentially, the cancer grows and causes problems wherever it is located. Talk to your doctors! do they think you are a candidate for treatment still, or should you go for hospice/palliative care? Good luck!