Bunnies will only ever respond to a small vocabulary of words however it is possible through constant repetition to teach them to respond to a few key words and phrases which can offer them gentle guidance to help control their behavior.
By far the most important word you can teach your bunny is their own name. This is key to getting their attention with an aim to giving them an instruction. To get them used to their name use it frequently in a positive manner such as calling them when you give them food or treats.
Then later when you need to stop them from doing something inappropriate start by saying their name in a firm voice followed by a command like No! You may have to say this a few times for it to sink in.
Another command that works well is 'get down' which can be used to let your bunny know you don't want them to climb on something or that you are going to move them of some furniture your bunny has climbed on. This can be an effective way of getting them off a surface without scrabbling away, scratching surfaces, and knocking things over.
Some people have even reported success using voice training to encourage their rabbits to use a litter tray regularly which can help to avoid toilet accidents on furniture like sofas.
This is a matter of repeating a word like 'Wee wee' when they are on the litter tray then using this to guide them that this where you want them to go.