Hello,

If I understand well, you are looking for a template. On my side, 
I used yatemplate coupled with auto-insert. Here is the part of 
configuration I have:

  (use-package yatemplate
    :ensure t
    :after yasnippet
    :config

    ;; Define template directory
    (setq yatemplate-dir (concat config-basedir 
    "/third_parties/templates"))

    ;; Coupling with auto-insert

    (setq auto-insert-alist nil)
    (yatemplate-fill-alist)
    (add-hook 'find-file-hook 'auto-insert)
    )

I use a template like the one attached which is place on the 
directory "<config-basedir>/third_parties/templates". I let you 
adapt but technically it should work with many adaptations.

Kind regards,
Sébastien