How do I add a sprint function in java?

So, I am currently playing around with Unity for the first time, and I am new to java as well. So I was wondering if someone would be so kind as to tell me how to make a sprint function, like hold down shift and ‘w’?

if (Input.GetButton(“Run”))
moveSpeed += runSpeed;

You will need to set a new input called run and bind it to shift under project settings/inputs.
Also if your new to java I highly recommend you go with C#

what is the run key?