\documentclass[a4paper,11pt]{article}

% Packages
\usepackage[utf8]{inputenc}   % for UTF-8 encoding
\usepackage{amsmath}          % for math symbols
\usepackage{graphicx}         % for including graphics
\usepackage{geometry}         % for setting page margins
\usepackage{cite}             % for citing references

% Page layout
\geometry{left=2cm, right=2cm, top=2.5cm, bottom=2.5cm}
\pagestyle{empty}

% Begin Document
\begin{document}
% Title
\begin{center}
    \LARGE \textbf{Title of Your Abstract Here} \\
    \vspace{0.5cm}
    \large \underline{First Author}$^{1}$, Second Author$^{2}$, Third Author$^{3}$ \\(please underline presenting author)\\
    \vspace{0.5cm}
    \small $^{1}$Institution/University, City, Country \\
    $^{2}$Institution/University, City, Country \\
    $^{3}$Institution/University, City, Country \\
\end{center}
\vspace{.7cm}
\normalsize
%Abstract text
The abstract text goes here. You may include ONE figure. The total length of the abstract (including title, references...) is limited to one page.\\
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\begin{figure}[h!]
    \centering
    \includegraphics[width=.3\textwidth]{image.png}
    \caption{Caption text goes here. }
\end{figure}
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% References (if any)
\begin{thebibliography}{9}

    \bibitem{example_ref1} First Author, Second Author, \textit{Journal Name} (year), \textbf{volume}, pages.
    \bibitem{example_ref2} First Author, Second Author, \textit{Journal Name} (year), \textbf{volume}, pages.
\end{thebibliography}

\end{document}