Subsection in frame with tcolorbox package

Question

I added thesubsection to the frame header but was not. I want to subsection the subsection in the image below as an automatic, not manually!

Here is my declaration

\newtcolorbox{boxtb}[2][]{enhanced,
before skip=2mm,after skip=2mm,
colframe=blue!75!black,colback=yellow!30!white,colbacktitle=red!10!white,breakable,
fonttitle=\bfseries,coltitle=black,attach boxed title to top left=
{yshift=-0.25mm-\tcboxedtitleheight/2,yshifttext=2mm-\tcboxedtitleheight/3},
boxed title style={boxrule=0.5mm,
frame code={ \path[tcb fill frame] ([xshift=-0mm]frame.west)
-- (frame.north west) -- (frame.north east) -- ([xshift=4mm]frame.east)
-- (frame.south east) -- (frame.south west) -- cycle; },
interior code={ \path[tcb fill interior] ([xshift=-0mm]interior.west)
-- (interior.north west) -- (interior.north east)
-- ([xshift=2mm]interior.east) -- (interior.south east) -- (interior.south west)
-- cycle;},
},
fonttitle=\bfseries,title={\thesubsection #2},#1}

Answer 1

If I understand you correctly, you want to use the tcolorbox for subsections. This can be done with the titlesec package, see e.g. here. UPDATE: Tried to match your updated question.

\documentclass{article}
\usepackage{xcolor}
\usepackage[explicit]{titlesec}
\usepackage[many]{tcolorbox}

\newtcolorbox{boxtb}[2][]{enhanced,
before skip=2mm,after skip=2mm,
colframe=blue!75!black,colback=yellow!30!white,colbacktitle=red!10!white,breakable,
fonttitle=\bfseries,coltitle=black,attach boxed title to top left=
{yshift=-0.25mm-\tcboxedtitleheight/2,yshifttext=2mm-\tcboxedtitleheight/3},
boxed title style={boxrule=0.5mm,
frame code={ \path[tcb fill frame] ([xshift=-0mm]frame.west)
-- (frame.north west) -- (frame.north east) -- ([xshift=4mm]frame.east)
-- (frame.south east) -- (frame.south west) -- cycle; },
interior code={ \path[tcb fill interior] ([xshift=-0mm]interior.west)
-- (interior.north west) -- (interior.north east)
-- ([xshift=2mm]interior.east) -- (interior.south east) -- (interior.south west)
-- cycle;} ,
},
fonttitle=\bfseries,title={\thesubsection #2},#1}

\renewcommand{\thesubsection}{\Roman{subsection}.}

% adapted from https://tex.stackexchange.com/a/226751/121799
\titleformat{\subsection}
  {}
  {}{0pt}
  {\begin{boxtb}{\hskip0.7em#1}\end{boxtb}}


\begin{document}

\section{A test section}

\subsection{A test subsection}

\subsection{Another test subsection}
\end{document}