So, to start off with commands, here are the basics. It is good to start with the basics before moving on to the Intermediate Commands, and finally, the Expert Commands. Here are the Basic Commands:
/gamemode s Turns the player into Survival Mode
/gamemode 0 Turns the player into Survival Mode
/gamemode c Turns the player into Creative Mode
/gamemode 1 Turns the player into Creative Mode
/tp {player's name} {your name} Teleports the player to you
/tp {your name} {player's name} Teleports you to a player
/weather clear Clears the weather
/weather rain Creates rain
/weather thunder Creates a storm
/time set {time of day} Changes the day
/time set {time of night} Makes it into night
/kill {player's name} A deadly superweapon, that can terminate any player.
/gamemode 0 Turns the player into Survival Mode
/gamemode c Turns the player into Creative Mode
/gamemode 1 Turns the player into Creative Mode
/tp {player's name} {your name} Teleports the player to you
/tp {your name} {player's name} Teleports you to a player
/weather clear Clears the weather
/weather rain Creates rain
/weather thunder Creates a storm
/time set {time of day} Changes the day
/time set {time of night} Makes it into night
/kill {player's name} A deadly superweapon, that can terminate any player.