Real conditionals

The Present Real Conditional is used to talk about what you normally do in real-life situations.
Both "if" and "when" are used in the Present Real Conditional. Using "if" suggests that something happens less frequently. Using "when" suggests that something happens regularly.
The Present Unreal Conditional is used to talk about what you would generally do in imaginary situations.
In the Present Unreal Conditional, the form "was" is not considered grammatically correct. In written English or in testing situations, you should always use "were." However, in everyday conversation, "was" is often used.
Only the word "if" is used with the Present Unreal Conditional because you are discussing imaginary situations. "When" cannot be used.