Don't ill-treat any amphibian. Bear in mind they might not have always been an amphibian and what happened to them could happen to you. Secondly, play your cards right and you may well break that curse and end up with a marriage partner, half the Kingdom, riches galore and so on.
It is not unusual to hear animals talking in the magical environment. Don't ask how they all seem to know fluent English. That is just the way it is and helps any English speaker in any case. Do listen to them. Something happened to them to make them speak. It pays to heed any warning they issue.
Good fortune favours the brave, the youngest of three, the step-daughter who is currently working her guts out in the kitchen and so on. It pays to befriend all of these groups. When they come into their fortunes, they will remember those who were kind to them.