Open Worldkiln
Use the Windows download. Open Worldkiln and create or open a project from Home.
Build a small floor
Place a few Blocks and a SpawnPoint above the floor. Keep the first World small so problems are easy to see. See Building.
Test it
Start Play mode. Check that the Player starts above the floor and can move. Stop Play to return to editing. Play changes are temporary. Save your authored work from the editor.
Add behavior
Follow Your first script to print a startup message. Use Projects and builds when you are ready to package the game.