Yes. It is usually diagnosed after finding elevated liver enzymes indicating injury. There are specific tests that find antibodies to the virus, and more specific tests that show how much virus is present in the body. Liver scans or ultrasounds can show if the liver is damaged and/or scarred. The ultimate gold-standard test is a liver biopsy, where a needle is inserted under imaging to get tissue.
Cirrhosis management. Yes. Cirrhosis of any cause needs ongoing management., incl. Blood tests, imaging, endoscopy etc. And hepatitis c treatment options have changed. Recomend you be seen by a hepatologist (liver specialist) or a GI with an interest in liver disease - call their office and see if they are offering hep c therapy - often through an affiliated 'mid-level' i.e. A nurse practitioner because of time.