It’s not so much correctness, more deciding what answer shall be chosen.
If you were adding, you would want to say “the sum of 0 numbers” is something that, if you add X to it, gives X”. That is easy. It is 0.
If you were multiplying, you would want to say “the product of 0 numbers” is something that, if you multiply it by X, gives X. That is easy. It is 1.
If you are taking the minimum, you want to say “the minimum of 0 numbers” is a value which, if you take the minimum of it and X, gives you X. That is easy. It is plus infinity.
In your particular case there are two problems. One is that the integer representations we use cannot represent plus infinity. You have to make a decision here - and replacing “plus infinity” with INT_MAX has a lot to be said for it. It makes it impossible to distinguish between “the minimum of 0 numbers” and, say, “the minimum of, say, 3 numbers all of which are INT_MAX”. But in the real world that often does not matter.
The second problem is that in the context of a program you may actually want to distinguish the “0 numbers” case. Then you need to realise that your alleged “min” function is actually returning two answers, not one: (1) are there more than 0 numbers? (2) if there are, what is their minimum?
Finally - the answer here is what you decide it to be, nothing else. There is no “right answer somewhere out there” which you are attempting to find. The decision is yours.