Undefined control sequence "\end{frame}" - latex

Question

I am totally new to Latex, I am seeing error at end of line \end{frame} , not able to figure it out why?
\documentclass{beamer}
% --------------------------------------------------- %
% Presentation info %
% --------------------------------------------------- %
\title{Test1}
\author{AMITH KOTIAN}
\date{January 2021}
\begin{document}
\maketitle
\section{Introduction}
\begin{frame}{HAND REHABILITATION SYSTEM}
\chaptype{ \LARGE \textbf {1.Design Consideration}}
\vspace*{0.5cm}
\begin{itemize}
\setlength{\itemsep}{3mm}
\begin{Large}
\item User safety must be guaranteed.
\item It can be easily worn.
\end{Large}
\end{itemize}
\end{frame}
\end{document}

Answer 1

The macro \chaptype is not defined. I have no idea what you might want it to do, but you must either load a package with defines it or define it yourself:
\documentclass{beamer}
% --------------------------------------------------- %
% Presentation info %
% --------------------------------------------------- %
\title{Test1}
\author{AMITH KOTIAN}
\date{January 2021}
\newcommand{\chaptype}[1]{{#1}}
\begin{document}
\maketitle
\section{Introduction}
\begin{frame}{HAND REHABILITATION SYSTEM}
\chaptype{ \LARGE \textbf {1.Design Consideration}}
\vspace*{0.5cm}
\begin{itemize}
\setlength{\itemsep}{3mm}
\begin{Large}
\item User safety must be guaranteed.
\item It can be easily worn.
\end{Large}
\end{itemize}
\end{frame}
\end{document}