Well, generally speaking, you may get burning eyes if you have dehydration. As we know that there are many factors which can lead to burning eyes, such as high eye pressure. And the dehydration can also lead to high eye pressure. So if you have this kind of symptom, you should just be careful about it. Well, to treat your burning eyes, of course, you need drink more water. And also, I will suggest you put some cool ice on your eyes, and do some cold compresses on your eyes. In that way, it can relieve your symptom. Also, you should eat a diet rich in fresh fruits and vegetables. You should know that these foods provide lots of antioxidants, especially vitamins A and C and then do a good job to your symptom. Anyway, just pay more attention to it.
Yes dehydration will cause burn eyes, but it's not the root of the problem.
The dehydration may be caused by high fever, or allergy.
Especially the allergy, it may cause burning and itchy eyes. Prevention is the best way to treat any allergy. There are both natural and medical ways to prevent allergy burning of eyes.
You need to drink much more water than the average, then if it won't work,check out whether you have a fever or allergy.
According to your description, I can see that there is something wrong with your eyes. However, burning does not equal dehydration because as you can see, a lot of diseases in relation to the eyes would generate burning eyes. So, what I recommend to you is trying to consult a doctor and find out what precisely led to your burning eyes, maybe it is dehydration.