My sister has cervical cancer. Should I be worried about it?

No increased risk. Cervical cancer is not one of the hereditary cancers. Almost all cervical cancers are caused by one of the human papilloma viruses (hpv). If you are having your annual exams and routine pap smears, any abnormal cells will likely be detected on the pap smear, which will allow plenty of time for appropriate treatment and prevention of cervical cancer.
Yes . She should know her stage & treatment options asap. A gyn oncologist can explain the surgery and if additional radiation or chemo treatments are needed. You should also make sure your pap smear and exam are up to date. Good luck.