There are several questions here on ELL that refer to the idiom "if you have any questions", but none of them touches upon why is it "you have" and not "you would have", when that sentence refers to the future.
As an example:
Teacher: Please finish this task until next Sunday.
Student: No problem. If I (would) have any questions, I'll ask you by email.
Is the student in this example correctly using would?
If not, why is it? Assuming the student doesn't have questions now, and would only have questions once they start working on the task, shouldn't there be a would?