Using the Server Console
Go to your Minecraft Server Panel and make sure the server is ON.
In the console, type
op <player_name>replacing <player_name> with the player’s name you want to OP.Press the Enter key on your keyboard for the command to take action.
NOTE: If the player you are trying to OP has a space in his name, you’ll have to put their entire name between quotes, like such op "RocketNode User".
Using the In-Game Chat
In order to use this method, you’ll have to already be an operator, which means you can give OP to another player.
Connect to your Minecraft server
Make sure you have OP permissions
Open the in-game chat and type
/op <player_name>replacing <player_name> with the player’s name you want to OP.Press the Enter key on your keyboard for the command to take action.
Revoking a Player’s OP
Open the in-game chat or the Console
Type
/deop <player_name>replacing <player_name> with the username of the person that will get their operator revokedPress Enter on your keyboard