In most cases, you'll need to pay. Viz provides a range of subscription plans to give you access to their manga library. However, they might have occasional promotions or free previews for certain titles.
Yes, usually you do. Viz often charges for accessing their manga content.
It depends. Some manga on Viz might be available for free, but for the majority, a subscription or payment is required to read them fully. They offer different packages and payment options depending on your needs.