Change in my diet

I have eaten a large breakfast but I mixed my snacks together.  The food was good which was a trap for me.  I made barbecued chicken, hot dogs, and mashed potatoes.  I was lucky not to have eaten more than I had.  But what messed me up was not eating healthy enough.  I ate a lot of protein when I should have eaten fruits and vegetables.  I need to eat more fruits and vegetables and more fiber.  My diet is not great so how do I go about changing it?