(I'm newbie , sorry for possibnly silly questions)
I heard bash has a capability of multitasking. I mean an ability to run a few terminals/console applications and switch between these (Ctrl+Alt+Fx??) .
is it possible in ubuntu subsystem in Windows 10
Yes, you can run apps in the background on Bash on Windows (see this useful guide).
Removed previous caveat since we recently introduced the ability for WSL to keep your daemons/background-services running even if you close all your Linux consoles: https://blogs.msdn.microsoft.com/commandline/2017/12/04/background-task-support-in-wsl/
Also, yes, WSL supports backgrounding tasks, running multiple sessions in different panes of a single Console via tmux/screen, or multiple Windows Console instances operating the same distro instance.
