You don't need filters for general use at all, and UV filters don't serve any purpose on digital cameras. They're a hangover from film.
You can use a UV filter, or a plain glass one, for protection if you want to. There's a lot of controversy about this. Many of us prefer a lens hood for protection, and only fit a clear filter in dodgy conditions - blowing sand/dust/spume etc - but others swear by them. I think you can safely make up your own mind about this because there's no right or wrong choice, but I don't advise you to use a cheap filter. Get a decent one. There's less risk of distortion and flare.