That I will always be average at my job.
I will never be good at it. Simply because I am not passionate about it. But then I also don't know what else is there which I like that can pay my bills.

There are many ways to pay your bills: some good, some bad, some easy, some hard, some legal, others not so much.
That being said, I advise you to try and find a job you like to do, because if you don't, sooner or later it's going to be impossible to get to work.

Gold luck

While I don't disagree with @Jilano's advice (work is so much better if it's something you truly enjoy), it's also important to remember that you don't have to be passionate about what you do for a living. Sure, it helps, but some people just won't find something like that no matter how hard they look. And that's okay! If you're content, it's not making you miserable, you make a living and can clock out and then go do the things you ARE passionate about, that's a pretty good spot to be in.

I grew up being told that no matter what, people just want me to "be happy." I put too much pressure on myself trying to figure that out. I'm much "happier" not worrying about how happy I am, and just living my life. I found that I became more passionate about the things I was doing, because I wasn't second guessing myself.

But don't hold yourself back either - if you crave something more, go for it. You only live once (probably)