Give him or her the same kind of food everyday.

You are facing a tough age for a power struggle about anything, much less food!  There are differing opinions, even among pediatricians, on how to handle this situation.  It's great that your child does not have other behavioral issues, that should make it easier to get through this problem.
One option is to have only what the family is eating available for meals.  If your child is doing well on his growth curve (ask his doctor if you don't know), then it is not a problem for him to occasionally go to bed hungry.  Another option (and my preferred one) is to have a backup selection that you know he will eat.  I would suggest requiring he taste whatever the family's main dish is.  If the child resists tasting, then he should simply sit with the family while the meal goes on.  If he will taste, but doesn't want to eat more, then have a backup option available.  Most children like peanut butter and jelly which is actually a relatively healthy option.  It's also something that a child can prepare for himself, maybe not at age 2, but soon.  The backup option should not require a lot of extra preparation by you, something that can be thrown in the microwave at most.
However you decide to proceed, it's great that you realize that engaging in power struggles over food is highly undesirable and not in anyone's best interests!

Jeanne H. Brockmyer, Ph. D.
education.com expert clinical child psychologist

You have to give him/her the same kind of food every time. Then he/she will eat new foods without any fight.

I don't think you caused this by not introducing new foods at an early age. My son is 3, almost 4, and he used to eat everything he was given. Now, as he gets older, I think he just wants to be able to make some choices of his own. At that age, they start to be a bit independent, and only have so many things they have a say in. What I do is this: Involve the child in making the choice of what is for dinner. I always give my son 2 options that are acceptable to me, and he picks the one he can deal with. Allow them to help cook it...this helps a ton because they feel proud of it, and will want to eat it. Also, I agree with making them sit at the table until everyone is finished eating. At this age, they have such "busy" lives, they want to be on the go and learning all kinds of new things, so they might feel like they are losing out on something else they could be doing. Also, after dinner, I try to play a fun game with my son if he eats a reasonable amount of his dinner. I hope this helps! I know how hard it was for me, and hope the stage passes quickly for you! Good luck!