\documentclass[12pt]{report}
\usepackage[utf8]{inputenc}
\usepackage[margin=1in]{geometry}
\usepackage{amsmath,amsfonts,amssymb}
\usepackage[none]{hyphenat}
\usepackage[nottoc, notlot, notlof]{tocbibind}
\usepackage{graphicx}
\usepackage{times}
\usepackage{pgffor} 
\usepackage{float}
\usepackage{multicol}
\usepackage[english]{babel}
%\usepackage{anyfontsize}
%\usepackage{extsizes}
%\parindent 0ex
\usepackage[hypcap=true,font={small,it}]{caption}
\captionsetup{belowskip=2pt,aboveskip=2pt}
%\bibliographystyle{IEEEtran}
\setlength{\parindent}{4em}
\setlength{\parskip}{1em}
\renewcommand{\baselinestretch}{1.5}
\renewcommand{\chaptername}{Chapter}
\newcommand\inv[1]{#1\raisebox{1.15ex}{$\scriptscriptstyle-\!1$}}
\newcommand{\latex}{\LaTeX\xspace}
\usepackage{import}
\usepackage{example}
 
\usepackage{makeidx}
\makeindex
 \usepackage{xpatch}
\usepackage{blindtext}
\makeatletter
\xpatchcmd{\@makeschapterhead}{%
  \Huge \bfseries  #1\par\nobreak%
}{%
  \Huge \bfseries\centering #1\par\nobreak%
}{\typeout{Patched makeschapterhead}}{\typeout{patching of @makeschapterhead failed}}
\xpatchcmd{\@makechapterhead}{%
  \huge\bfseries \@chapapp\space \thechapter
}{%
  \huge\bfseries\centering \@chapapp\space \thechapter
}{\typeout{Patched @makechapterhead}}{\typeout{Patching of @makechapterhead failed}}
\makeatother
 
 \begin{document}
 \pagenumbering{roman}
%\frontmatter
 \input{chapter/title}
 \setcounter{page}{1}
 
\chapter*{\centering Certificate of Approval}
\addcontentsline{toc}{chapter}{Certificate of Approval}
\input{chapter/certificate.tex}
\clearpage
\chapter*{\centering Declaration}
\addcontentsline{toc}{chapter}{Declaration}
\input{chapter/declaration.tex}
\clearpage
\chapter*{\centering Acknowledgement}
\addcontentsline{toc}{chapter}{Acknowledgement}
\input{chapter/acknowledgement.tex}
\clearpage
\chapter*{\centering Abstract}
\addcontentsline{toc}{chapter}{Abstract}
\input{chapter/abstract.tex}
\clearpage
    \tableofcontents
    \listoffigures
    \listoftables
    \clearpage
\pagenumbering{arabic}
    \chapter{Introduction} 
    \input{chapter/introduction}
   
    \chapter{Literature Review}
    \input{chapter/literature review}     
    
    \chapter{Methodology}
     \input{chapter/methodology}
     
    \chapter{Results and Discussions}
    \input{chapter/results}
    
    \chapter{Conclusion}
    \input{chapter/conclusion}
    
    
    \addcontentsline{toc}{chapter}{References}%
    \bibliographystyle{IEEEtran}
    \bibliography{IEEEabrv,bibliography}
    
 \appendix
\chapter{Source Code for Application Interface}
    \input{chapter/appendix}
 \end{document}