Do You Have Advice About Dialogue?

When in doubt, do a scene in dialogue rather than through narrative. This will help keep the pacing faster.
Practice writing dialogue without any tags or setting descriptions; see if you can make each character SOUND like themselves without any other clues. Of course, you want to include the tags in the actual manuscript, but it’s good practice to learn to write characters who are identifiable with how they speak.
Keep it snappy, when possible.
Avoid dialects or trying to write a thick accent. Instead, characterize your characters with the words they choose, the length of their sentences, that kind of thing.
Go listen to some people talk and write down what they say! You don’t want to recreate this exactly, but it can be very illuminating to see how people really speak.