yes you can you just need a good plan to beat them

well, look ebay and amazon are the sites that are in the market from a longer time, you can beat them but you need to have a proper plan on how to ?? If you are a begineer and just entered into the market it might look tough but again it is not impossible you need to build up a huge plan in order to do this !!

Do you mean actual Ebay and Amazon? If yes, I can tell you without checking that they do have immense amount of backlinks. Of course you can compete even with these giants and get past them, but it's going to take a bit of work. However, without knowing any details we can just state that in principle this is possible. I'd help if we knew what kind of keyword you're talking about.