How could I exit Vim, not :q, and then go back to continue editing?
Answer
Assuming terminal Vim on a flavor of *nix:
To suspend your running Vim
Ctrl + Z
will suspend the process and get back to your shell
fg
will resume (bring to foreground) your suspended Vim.
To start a new shell
Start a subshell using:
:sh
(as configured by)
:set shell?
or
:!bash
followed by:
Ctrl+D (or exit, but why type so much?)
to kill the shell and return to Vim.