Use WASD keys to move your Pointer and F to break a block. Space to go change terrain. go to the next chunk. Use the options menu on the top to get access to the options menu which is the mode changer (more will be added in later updates).Default Mode is Normal. Blocks can not be placed.
Thank to Mattant Programming for the tutorial in youtube Link is given below:- https://www.youtube.com/watch?v=rolOxQvDLUU He says that this tutorial is outdated but it is working well.