It's very unlikely Trump will be elected to the presidency because of his rather extreme rhetoric. However even if he does, he will moderate his policies to be a bit more palatable to more moderate voters. At the moment he's exploiting extreme right-wing comments to try to appeal to hard-line Republicans in order to be nominated.
He cannot possibly enforce any of the anti-Muslim policies he's proposing. If for no other reason than the fact that it would offend Saudi Arabia.