\documentclass[
	12pt, % Default font size, values between 10pt-12pt are allowed
	%letterpaper, % Uncomment for US letter paper size
	%spanish, % Uncomment for Spanish
]{fphw_assignment_toc}
\usepackage{my_packages}
%------------------------------------------------------------------------------------
\title{My Assignment \texttt{\#}1}        % Assignment title
\author{My Name}    % Student name
\roll{My Roll}                    % Class roll
\class{My Class}              % Class
\session{My Session}             % Session
\email{me@domain.edu}
\date{Today}        % Due date
\institute{Department of Physics}              % Institute or school name
\course{Course Name}                            % Course or course name
\professor{Teacher Name}                                           % Professor or teacher in charge of the assignment
%------------------------------------------------------------------------------------
\addbibresource{ref.bib} 
\setcounter{secnumdepth}{-2} 
%\renewcommand{\thesection}{}  % https://tex.stackexchange.com/a/30202/114006
%------------------------------------------------------------------------------------
\begin{document}
\maketitle
\pagenumbering{gobble}           % to remove the page numbering
\newpage
\pdfbookmark[section]{\contentsname}{toc}
\tableofcontents
\newpage
\pagenumbering{arabic}          % to start the page numbering
%-----------------------------------------
\section{Problem 1 Name~\cite{book:zettili}}
\begin{problem}
  \lipsum[1][5-6]
\end{problem}
\subsection{Solution:}
\blindtext
\subsubsection{(a)}
\lipsum[2][5]
\subsubsection{(b)}
\lipsum[3][5]
\section{Problem 2 Name~\cite{book:zettili}}
\begin{problem}
\lipsum[4][5-6]
\end{problem}
\subsection{Solution:}
\blindtext
\begin{figure}[!ht]
  \centering
  \includegraphics[scale=.3]{example-image-empty}
  \caption{ \lipsum[5][2]\cite{book:griffiths}}
  \label{fig:fig1}
\end{figure}
\newpage
\section{Appendix}
\begin{problem}
  \centering  \lipsum[6][3]
\end{problem}
{\footnotesize
\blindtext \cite{book:balakrishnan}
}
\newpage
\phantomsection   % 
\printbibliography[heading=bibintoc, title={References}]
\end{document}