\documentclass{article}

\usepackage{pgfplots}
\usepackage{pgfplotstable}
\usepackage{booktabs}
\usepackage{array}
\usepackage{colortbl}


\pgfplotstableset{% global config, for example in the preamble
  every head row/.style={before row=\toprule,after row=\midrule},
  every last row/.style={after row=\bottomrule},
  fixed,precision=2,
}

\begin{document}
\begin{table}[h!]
	\centering
	\caption{Ceci est un tableau créé à partir de données extraites}%
	\label{tab:DataTable}
\pgfplotstabletypeset[
%column type=r
  columns/freq/.style={column name=Frequency (Hz), column type=l},
  columns/conc/.style={column name=Concrete},
  columns/lino/.style={column name=Linoleum},
]{2020-02-01sep.txt}
\end{table}





\begin{figure}[h!]
\centering
\begin{tikzpicture}
\begin{axis}[
    xlabel={Frequency (Hz)},
    ylabel=Absorption Coefficient,
    legend pos=south east,
    legend entries={Concrete,Linoleum},
    ]
  \addplot table [x=freq,y=conc] {2020-02-01sep.txt};
  \addplot table [x=freq,y=lino] {2020-02-01sep.txt};
\end{axis}
\end{tikzpicture}
\end{figure}

\end{document}