discuss

The verb "discuss" is not followed by any preposition:

• You should discuss this with your doctor. 

• She claims she would like to discuss the issue with her political opponents. 

• If you want to contact the company to discuss their decision, that is your call. 

• The seminar will discuss how to help kids make healthy choices. 

• Don't be afraid to show your emotions and (to) discuss what really matters to you. 

The Oxford dictionary clearly points this out- read their explanation here. 

See more examples illustrating the dictionary definitions: 

• Cambridge dictionary

• Oxford learners dictionary

• Collins dictionary