\documentclass[10pt]{beamer}
\usetheme[progressbar=frametitle]{metropolis}
\begin{document}
\begin{frame}{Table \begin{frame}
\frametitle{Table of content}
\setbeamertemplate{section in toc}[sections numbered]
\tableofcontents
\end{frame}
\section[Recherche arborescente de Monte Carlo \newline
{\footnotesize Monte Carlo Tree Search ou MCTS}]{Recherche arborescente de Monte Carlo}
\end{document}
![alt text][1]
[1]: https://texnique.fr/osqa/upfiles/Screenshot_2022-05-21_at_21.00.14.png