\documentclass{article}

\begin{document}
	\section{Introduction}
	\subsection{Kernel}
	\subsection{Concepts}
	\section{Types of Operating Systems}
	\section{Process Management} hardware file memory
	\section{Memory Management}
	\section{File Management}
	\section{Handling of I/O}
	\section{Interrupt Handling}
	
\end{document}