If you are going to do an amphibious invasion of a beach head, you can expect 99% of the time, the presence of some sort of beach defense. For Iran to do an operation like that, the country would have already been fully mobilized to protect the coasts.
The beach needs to be approached with amphibious armored vehicles, perhaps additional artillery support in the form of 23mm guns from corvettes or just don't bother at all because you'll get shredded. Hovercraft and infantry can approach from behind.