Well when I was young, I remember that my father wouldn't let me get up from the dinner table until my plate was clean. I can't do that to my daughter because I don't want her to feel forced to eat. There's always an option (Although the option is usually, eat some more or go to bed). I never will make her eat all of it. I don't want her to over eat. She has to eat most of everything though.
As for meat, sometimes she will eat it, sometimes not. It depends on what it is. If it's chicken, she will almost always eat it. Beef is something I struggle with, but I'm not too worried about meat. Try making meaty meals that are fun to eat. Kyleigh LOVES to eat tacos. Also, if it's something like chicken tenders or hotdogs, some kind of a dip is a MUST. Ketchup is my best friend, along with a close friend named Ranch dressing.
One thing that she absolutely LOVEs to eat is shepherd's pie. It has beef, veggies, potatoes, and cheese. Can't go wrong with anything topped with cheese. If you want a recipe, just ask.
It is true, some things they will never eat. But it's important for YOU to eat what you are trying to feed her too. If she sees you enjoying the same thing, she will be more likely to try it.
You're going to have to keep offering her the same kinds of food repeatedly so she can get a taste for it. Remember, her taste buds aren't fully developed yet. There are plenty of things I would never eat as a child but love to eat now.