Write an article based on this "Find out if you are eligible. Learn about Parts A, B, C, and D. Contact the Social Security Office. Updating your plan."

Article:
American citizens who are 65 years of age and older are generally eligible for Medicare. You also need to have lived in the United States for at least five calendar years prior to receiving benefits. You also need to have been employed for 10 years in a workplace that was covered by Medicare. If you are not sure if that's you, you can contact your employer to ask.  If you meet the above criteria, you likely will not have to do anything to receive your coverage. Typically, a Medicare card will be mailed to you prior to your birthday. You may qualify for Medicare if you are under 65 but have specific medical ailments. If you have End Stage Renal Disease, you qualify. You are also eligible if you have received Social Security Disability Income (SSDI) for more than 24 months. If you suffer from ALS, you can receive Medicare after only one month of SSDI. There are several different parts to Medicare insurance. Part A is basic hospital coverage, and this is what adults 65 and older will automatically be enrolled in. Part B is more comprehensive medical coverage, and you may have to enroll in this plan. It is optional, and you do not have to participate.  If you are a former railroad employee and are receiving benefits from the Railroad Retirement Board, you will automatically be enrolled in Parts A and B. If you are permanently disabled or have ALS, you automatically get Parts A and B. Part C is called the Medicare Advantage Plan and is more comprehensive than Parts A and B. This is optional, but you must be enrolled in Medicare to enroll in Part C coverage. It is available through private insurance companies. Part D is also provided through private insurance companies. Like Part C, it is optional. Part D covers prescription medications. Once you have determined your eligibility, it is time to make sure that you are enrolled in Medicare. The Social Security Office handles Medicare enrollments. The easiest way to have your information processed is to use the online form provided by the Social Security Office. No documentation is required, and it should take you less than 10 minutes to apply.  If the Social Security Office needs further information, they will contact you. Otherwise, you can expect to receive your Medicare card in the mail. If you do not want to enroll online, you can visit your local Social Security Office or call them to make an appointment with a Social Security representative. Although most people will automatically be enrolled, some might have to sign up for Medicare. If you are not receiving Social Security benefits (for example, because you are still working), you will need to sign up for Parts A and B. Also, if you live in Puerto Rico and want Part B, you will need to enroll. To update your plan, enroll, or make any changes, you can contact your local Social Security Office or use the online forms.