You must get a mod. A few examples are factions, bigbrother, eagleeye, etc.
You can place blocks but not make them.
Place track like this. - and | = Track __ | or __ |
No, you can only place and destroy blocks.
Right click where you want to place it, make sure there is enough room for it.
There are no fireball potions in Minecraft but to make a fire charge you place a coal, gunpowder and blaze powder anywhere on the crafting grid to get 3 charges.
To make TNT, place 5 gunpowder and 4 sand
Make a crafting bench\table using 4 pieces of woodplanks, place it in the world, and right click on it to get a 3x3 board. There you can place different objects in a way to get a tool. You can find crafting recepies on minecraft wikis.
yes it does save what you make but the minecraft demo also saves but doesn't let you craft, place or destroys things after 100 minutes which is when the demo get expired.
You cant make a couch as such, but you can place a stair block and than put signs on the sides.
wait for night or dont place down torches
place 2 wooden placnks going vertically in the crafting table :)
To make a lever, place a stick above a block of cobblestone, in your crafting slot or on a crafting table.