I want to get the iPhone 5c but I want to stay with my prepaid plan?

Can I just go to the apple store and purchase an iPhone 5c and go on Verizon's website and activate it? I pay 50 dollars a month for unlimited text/call/internet can I still keep paying 50 a month or will Verizon make me change my plan?

Thats not good

Yes you can, but the catch is you have to buy the phone at the full price. Which is around 500$

You could buy it factory unlocked and do that. The cost of the phone is significantly higher though doing it that way.

I'm pretty sure Verizon does not allow LTE phones on prepaid plans. For most you have to actually do some software hacks to get it to work on 3G only.

Otherwise if you want to check out what other prepaid offers are out there, I recommend http://www.allprepaidplans.com