I want to convert this image into TikZ.
I already have the following code, but I don't know how to put the numbers at the vertices and how to put that red bar inbetween 2 and 3. Could someone please explain how to do this?
\documentclass{article}
\usepackage{xcolor}
\definecolor{navyblue}{rgb}{0.0, 0.0, 0.5}
\usepackage{
pst-poly,
pstricks-add
}
\usepackage[
% locale = DE,
round-mode = places,
round-precision = 2
]{siunitx}
\ExplSyntaxOn
\cs_new_eq:NN
\calc
\fp_eval:n
\ExplSyntaxOff
% calculations
\newcommand*\Angle{\calc{360/\sides}}
\newcommand*\sidelength{\calc{2*\radius*sin(pi/\sides)}}
\newcommand*\radiusI{\calc{\radius*cos(pi/\sides)}}
\newcommand*\areaI{\calc{pi*\radiusI^2}}% not used
\newcommand*\areaC{\calc{pi*\radius^2}}% not used
\newcommand*\areaRatio{\calc{cos(pi/\sides)^2}}% not used
\psset{dimen = middel}
\begin{document}
% constants
\newcommand*\sides{5}
\newcommand*\radius{3.5}
\begin{center}
\begin{pspicture}(-\radius,-\radius)(\radius,\radius)
% centre
\pnode(0,0){C}
% regular polygon with dots at corners
\rput(C){%
\PstPolygon[
PolyNbSides = \sides,
unit = \radius,
PolyRotation=18,
linecolor = navyblue
]
}
{\psset{linecolor = gray}
% circumscribed circle
\pscircle(C){\radius}}
\end{pspicture}
\end{center}
\bigskip
\end{document}