Absolutely fine. It's usually recommend to do 1 or 2 above, 2-3 in line with predictions, and one slightly below. Obviously not possible in all cases and there should be more to deciding than grade requirements, but just as a rough ballpark
Is it fine to put down 3 choices which exactly require what you are predicted?
Yes, if you feel confident that's perfectly fine although I'd recommend at least one that's lower. Personally I went with 2 higher than my grades but that I really wanted (I got an offer from one of them), Then 2 with my predicted grades and one below (I got offers from all of these - woop woop). The most important thing is to like all the universities you put down, you will probably have a favorite or some you prefer but it's good to like them all as you could end up at any of them.
It's a scary process dealing with all this UCAS stuff but try and trust yourself and how you're feeling. I'm sure it'll all go great! If you have any more questions please feel free to ask!