Yes. I know what I should do.
Change balanced plan and Power saver to both
Turn off the display NEVER
Put the computer to sleep NEVER.
So why the monitor goes blank (Black) until I touch the mouse or keyboard.
Some monitors have a built in shut down after a certain period of inactivity. This helps prevents screen burn.
Even if you set up a screen saver you will still have to hit a key or move the mouse to resume normal use, so you will still have the same situation. Moving the mouse or hitting a key is really not a much of a problem to live with.
Also it may be possible to use a macro scripting such as Autohotkey to send a keystroke after a certain period of inactivity. A "keep alive" type of thing. There may be some on Autohotkey forums. Here's one I found:
Keep Alive! Script - Scripts - AutoHotkey Community
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