Hi Zhijie,
Thanks for your registration comments!   You will be happy to know that ChimeraX does have Side View.  You can choose it from the menu: Tools… General.  

<http://rbvi.ucsf.edu/chimerax/docs/user/tools/sideview.html>

To make a tool (Side View, etc.) start automatically every time you start ChimeraX, right-click in that tool (or Ctrl-click on some systems) to show the context menu, and from that menu choose “Start at ChimeraX Startup”

<http://rbvi.ucsf.edu/chimerax/docs/user/window.html#context-menu>
<http://rbvi.ucsf.edu/chimerax/docs/user/window.html#tool-context>