First conditionalTo talk about something that is possible in the future.
You use the present simple in the If clause and a future tense in the main clause.
If the government doesn’t change course, things will get worse.
You can also use a modal verb or the imperative in the main clause.
If I see her, I can give her your message.
If you have any problems, give me a call.
You can use unless instead of if not in the If clause.
You can’t park here if you don’t have a permit.
You can’t park here unless you have a permit.