Larger ships cannot dock right in the port. In these cases, your ship will anchor at sea and ferry you to shore by tender. These small crafts make frequent round trips, so you can get back aboard ship at various times. Just ask a crew member for the schedule. A cruise can be an ideal vacation option for an older or disabled traveler.
New ships are wider and more accessible, so keep that in mind when choosing a cruise.
If your goal is to enjoy a relaxing getaway where you can simply pamper yourself, consider a transoceanic crossing or a cruise to nowhere. When you cruise, each ship will publish a daily calendar of events and activities. Plan your day around it or with it. It's all up to you. The first cabins to go on a cruise are the most expensive and least expensive, and since all passengers are entitled to the same level of service, plan well in advance to reserve the cabin that's right for your needs and budget.