The following videos represent general tips for using your computer and are valid for all editing programs.
Handbrake is a free program that can make high quality H.264 and H.265 video. I use it to make all my tutorial videos as it can compress them to very small files and still look good. You can also use it to remake files which do not work properly in your editing program. You can download Handbrake here: https://handbrake.fr/
Making subtitles is really quite boring, as you have to transcribe the text and line it up to speech. On this page I have a couple of videos on how to make this easier with different editing programs.
A short collections of tips for using Windows when editing, including Stiky notes, taking quick screen shots, show just the files you want in Windows explorer, making system images and cleaning up temporary files.
This short video shows how I make screen recordings with a free screen capture program called OBS. OBS can do a lot more than I describe here and you can use it to broadcast live to the Internet. However it can simply record the screen which you can then later edit in your editing application. You do have to make sure to change some basic settings as well just to make sure your editing program will work properly with it.