Hello,
1) You can adjust the slider height/width using the slider settings depending on the type of the slider. Read the Revolution slider documentation https://www.sliderrevolution.com/documentation/module-layout/#breakpoints
https://www.sliderrevolution.com/faq/responsive-content/
2) What element do you use to add the video? You can limit the width of any element by the column width where it’s placed.
Regards