Is is allowed to be critical of my wife?
I hope you are not as serious as I think you are, why would you be so critical of her?
I don't like her cooking.
When you married her you committed to care and support her, not criticize everything she does. Your criticism will probably hurt her feelings. Why don't you do the cooking if you don't like how she does it?
I want my wife to be a better cook. Just because she was a fifth grade drop out doesn't mean she can't learn how to cook for me.
You should be kinder, tell her to look at recipes on Youtube which is where I learn how to cook different things. Harsh words won't be a good sign your marriage is going to be working out in the end either. Support each other in everything you do in a calm manner.