I am looking for suggestions

I am brand new to this and not techie at all – yet! I just set up my www.remarpro.com site and am looking into plugins for a shopping cart/ecommerce store. ( I assume they are the same thing-please let me know if I am wrong) So far, it is just digital products but I will be adding physical products down the line. What is the easiest to install and set up plug in that will do the job for a very tech-challenged person like me? I am willing to go with something that only does digital download sales for now as long as it is easy to change down the line. But above all-EASY! Cheap or free is also good for the time being. Any suggestions?
Colleen