I am citing a figure from paper. I inserted \cite{..} in the caption of the figure. The figure is referenced as [1], although it is in middle of the document.
\documentclass[12pt,a4paper]{report}
\setcounter{tocdepth}{5}
\setcounter{secnumdepth}{5}
%\renewcommand{\algorithmicforall}{\textbf{for each}}
\usepackage{graphicx}
\usepackage{indentfirst}
\usepackage{hyperref}
\usepackage{color,soul}
\usepackage{amsmath}
\usepackage{algorithm}
%\usepackage{algorithmic}
\usepackage{algcompatible}
\usepackage{booktabs}
\usepackage{caption}
\usepackage{tikz}
\usepackage[english]{babel}
\usepackage{natbib}
\usepackage[final]{pdfpages} %for embedding another pdf
\usepackage{setspace}
\captionsetup[table]{skip=10pt}
\definecolor{lightblue}{rgb}{.80,.85,1}
\sethlcolor{lightblue}
\usepackage{verbatim}
\usepackage{parskip}
\usepackage{enumitem}
\begin{document}
%\renewcommand\bibname{References} %Renames "Bibliography" to "References" on ref page
%include other pages
\input{chapters/title.tex}
\input{chapters/certificate.tex}
%\input{./declaration.tex}
%\input{./dedication.tex}
%\input{./acknowledgement.tex}
%\input{./abstract.tex}
\pagenumbering{roman} %numbering before main content starts
\tableofcontents
\listoffigures
\listoftables
\newpage
\pagenumbering{arabic} %reset numbering to normal for the main content
\chapter{Introduction}
\input{chapters/Chapter1.tex}
\chapter{Literature Review}
\input{chapters/Chapter2.tex}
\chapter{Techniques Used}
\input{chapters/Chapter3.tex}
\begin{comment}
\input{./chapter_4.tex}
\input{./chapter_5.tex}
%\input{./appendix.tex}
%\input{./references.bib}
%\mbox{}
%\nocite{*}
%\bibliographystyle{ieeetr}
%\printbibliography
\end{comment}
\newpage
%\addbibresource{reference.bib}
%\renewcommand{\thepage}{}
\bibliography{reference}
\bibliographystyle{unsrt}
\end{document}
