\documentclass[border=1pt]{standalone}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{fourier}
\usepackage{tikz}
\usetikzlibrary{arrows.meta}

\begin{document}

\begin{tikzpicture}[>=Stealth, node distance=3cm, 
  every node/.style={circle, draw, minimum size=1cm}]

% Węzły na okręgu
\foreach \i/\name in {1/$c_1$, 2/$c_2$, 3/$c_3$, 4/$c_4$, 5/$c_5$, 
  6/$c_6$, 7/$c_7$} { \node (\i) at ({360/7*(\i-1)}:3cm) {\name};
}
% Krawędzie
\draw[->] (1) -- (2);
\draw[->] (1) -- (5);

\draw[->] (2) -- (1);
\draw[->] (2) -- (3);

\draw[->] (3) -- (4);

\draw[->] (4) -- (5);
\draw[->] (4) -- (6);

\draw[->] (5) -- (2);
\draw[->] (5) -- (6);

\draw[->] (6) -- (4);
\draw[->] (6) -- (7);

\draw[->] (7) -- (1);
\draw[->] (7) -- (6);
\end{tikzpicture}

\end{document}
