yes you pay once and you have it all
Yes there is single player, and multiplayer.
Not on single player. On Multiplayer you can though.
beacons are used in minecraft for getting some potions on you and knowing where your home is on single player
No, only if you want to. That's why it has Single player and Multiplayer buttons.
In single player you cannot open the chat box without mods. In multiplayer you press 'T'.
No, multiplayer has no effect on your already existing single player worlds.
No, but you can play on classic single player and if you have a account you can play on multiplayer classic
Play it in survival mode or creative mode. Don't press the multiplayer mode.
Version 10.0 doesn't exist just yet. but you play single player just as you would on multiplayer but just with one person... you.
There are single player mods that enable this as a command. But most are for multiplayer if you are searching the plugin: WorldEdit is the most chosen
Single player in Single Player, and multiplayer in Multiplayer.
Survival and creative single and multiplayer