Chromium browser does not give an graphic interface where user can create a second profile, but you can do it from command line by giving it option --user-data-dir, for example
chromium-browser --user-data-dir='~/.config/chromium2'
In Ubuntu or Debian system the default user-data-dir for Chromium browser is ~/.config/chromium
You can also add another launcher to panel besides the original Chromium Browser Icon, and modify the command property to
/usr/bin/chromium-browser --user-data-dir='.config/chromium2' %U
This time please use '.config/chromium2' but not '~/.config/chromium2', otherwise it will create a ~ folder in your home directory!