\documentclass{article}
\usepackage{changepage}
\usepackage{blindtext}

%% \newenvironment{envname}{start}{end}

%Indent 20 pts and decrease font 
\newenvironment{Example}
{
   \vspace{10pt}
   \begin{adjustwidth}{20pt}{0pt}
      \begin{small}
}
{ 
       \end{small}
   \end{adjustwidth} 
   \vspace{10pt}
}

\begin{document}


\blindtext
\begin{Example}
   \blindtext
\end{Example}
\blindtext


\end{document}
