As @DavidCarlisle has already suggested in a comment, you could place all three tables in a single table* environment. In the following code, the tables and their associated \caption statements are "wrapped" in minipage environments. The three tables employ tabularx environments with overall width \linewidth, to assure that they occupy the full width of the enclosing minipage environments.

\documentclass[conference]{IEEEtran}
\usepackage{tabularx}
\usepackage{newtxtext,newtxmath} % optional
\begin{document}
\begin{table}
%% first minipage
\begin{minipage}{\columnwidth}
\caption{Single-column wide}
\begin{tabularx}{\linewidth}{|{5}{X|}}
\hline
& & & & \ \hline
& & & & \ \hline
& & & & \ \hline
\end{tabularx}
\end{minipage}
\hfill
%% second minipage % observe: no blank line above this line
\begin{minipage}{\columnwidth}
\caption{Single-column wide}
\begin{tabularx}{\linewidth}{|*{5}{X|}}
\hline
& & & & \ \hline
& & & & \ \hline
& & & & \ \hline
\end{tabularx}
\end{minipage}
\bigskip
%% third minipage
\begin{minipage}{\textwidth}
\caption{Double-column wide}
\begin{tabularx}{\linewidth}{|{5}{X|}}
\hline
& & & & \ \hline
& & & & \ \hline
& & & & \ \hline
\end{tabularx}
\end{minipage}
\end{table}
\end{document}
table*(not related butpdoes not mean end of document, but float page) – David Carlisle Nov 14 '22 at 01:26