This post is old, the accepted answer doesn't concern about terminal buffer.
The accepted answer use session to do the trick, but session can't completely restore terminal buffer:
A terminal window will be restored when using a session file, if possible and
If "terminal" was removed from '...
To see window numbers you have to setup statusline (:h statusline), for example:
set statusline+=%([\%R%M]\ %)
set statusline+=%(\ %y%)
See winnr() function in the first line.
To switch to the window with that number you can use built-in 2 C-ww
You can add ...