Something I've heard a lot over my years of teaching is 'It's too hard!' or 'I can't do it!'
Trying or wanting to learn a whole piece or even four bars can initially seem overwhelming so the first thing would be to make sure the piece you are trying to play is within your reach and not too difficult too soon. Learning to play with two hands can take time so start with something very easy and work up from there.
One way to overcome coordination problems would be to break down the piece into small sections, as Outin suggested. When students used to say to me that something was too hard, I would ask them if they would say this if I was only giving them one bar to learn. I would say, supposing this piece was only that first bar that you say you can't do, would you say it is too hard then? This puts things into perspective and takes away the overwhelming feeling of overload.
Baby steps is the answer here. Take baby steps, remembering that a journey of a thousand miles begins with one small step.
Good luck!
Topic: How to improve on two hands playing?