I downloaded scrabble and when I enter a word, How do it submit it in the game and get new tiles.. I've tried all the button's and nothing is happening. I haven't even started yet and i'm struggling :)

The Scrabble3D-wiki should be a good starting point for such issues. Click on the question mark in the toolbar to connect online. "Next player" is what you are looking for. Either used with toolbar button beneath "new game" or per menu>game>next player.