There's a way to launch a process(continuously) in emacs? For example, imagine ruby REPL, I expect launch the command "irb" in emacs and it should be in some some kinda of separated tab or buffer.
For the specific case of REPLs in Spacemacs you can start one for any supported language with SPC m s i then explore SPC m s prefix command for all the commands to interact with the REPL.