pencil smoothing and correction

Dear Adobe,

I am having a little bit of trouble with some of the tools on Animate, specifically the smoothing tool.

In another program, Medibang, I am able to use the correction function to make arcs more rounded when I am drawing. Is there a similar tool in animate so that jerky hand movements are reduced. 

I have read and watched several tutorials on the topic of the brush tool, but none of the videos or articles that I could find explained how to apply line correction.

Also, I am not sure how to add keyframes and make them smaller in width.

Thank you for your time.