There is now maybe easier way to do screencasts and videos

OBS
Open Broadcaster Software

https://obsproject.com/fi?fbclid=IwAR38aJ3LZNDwquAallyJ7e0mxMUKY7YRiJgxpfSOvXfhyZ0rUnonh35J7nY

 

Or this:

VokoscreenNG: Open Source Screencasting Tool

https://itsfoss.com/vokoscreenng/?fbclid=IwAR19uXT422WIlpYYYolEQpJQUBhlwxi6ZUkQGv1sbmcAvuwzb9InBU5Gyig

For video editing there is also Kdenlive, you can install it like this

Open terminal, write

sudo apt-get update

Press Enter

sudo apt-get install kdenlive

If it wants to install addition software packages say yes to all .

 

Video recording and making the old school way:

Ask TWIL: How to Make a Screencast on Ubuntu / Linux

By the way, one of the best video editors  in linux and my favourite is Kdenlive .