As mentioned by CA, solar panels and an appropriate controller are only part of the issue. You need to size a battery bank for your needs. Batteries are heavy, take up a lot of space, are expensive and most need to be replaced every few years.
You really need to do an energy audit based on your expected and desired needs. You will quickly find that controlling utilization can greatly reduce your need for a major solar system and expenses. In my case, I do not use the microwave, electric coffee maker or similar appliances. I have a melitta coffee maker system that makes great coffee from water I heat on the stove. Anyway, you should be able to find online RV electrical calculators to estimate your system needs.
Solar is usually a standalone system with a controller that wires directly into your battery bank. You RV should already be configured for shore power, alternator and addition of a generator. It may also be pre-wired for solar. In any case, since you are asking very basic questions, you should leave the installation to the vendor.