\documentclass[]{standalone}
\usepackage[]{graphicx}
\usepackage{tikz}
\usepackage{pgfplots}
\pgfplotsset{compat=1.17}
\tikzset{>=latex}
\usetikzlibrary{arrows,arrows.meta}
\usepackage{steinmetz}
\newcommand*{\equal}{=}
\usepackage{tikz-3dplot}
\usetikzlibrary{decorations.markings}
\tikzset{->-/.style={decoration={
markings,
mark=at position #1 with {\arrow{>}}},postaction={decorate}}}
\begin{document}
\begin{tikzpicture}
\begin{axis}[
width=7cm,height=7cm,
xmin=0,xmax=1,
ymin=0,ymax=1,
grid=both,
%grid style={line width=.1pt, draw=gray!10},
major grid style={line width=.3pt,draw=gray!70},
axis lines=middle,
%minor tick num=5,
xtick = {0,1/2, 1},
ytick = {0, 1/2,1},
% xticklabels={$-\sqrt{3}$, $0$, $\sqrt{3}$},
% yticklabels={$-\sqrt{3}$, $0$, $\sqrt{3}$},
enlargelimits={abs=0.05},
ticklabel style={font=\tiny},
xlabel={$x$},
ylabel={$y$},
xlabel style={font=\tiny, at={(ticklabel* cs:1)},anchor=north},
ylabel style={font=\tiny, at={(ticklabel* cs:1)},anchor=west},
]
\draw (axis cs:0,0) node[below=4pt,left=0pt] {\tiny$0$};
\addplot[domain=0:1,samples=100] {7*(x-x^2)/4};
\addplot[domain=0:1,samples=10] {x} ;
\fill (axis cs:3/7,3/7) circle [radius=0.02];
\draw [thick, ->-=0.5] (0.95,0.083125) -- (0.083125,0.083125) -- (0.083125,0.133377) --
(0.133377,0.133377) -- (0.133377,0.202278) -- (0.202278,0.202278);
\draw [thick, ->-=0.5] (0.202278,0.202278) --
(0.202278,0.282383) -- (0.282383,0.282383) -- (0.282383,0.354625) --
(0.354625,0.354625) -- (0.354625,0.400516) -- (0.400516,0.400516) --
(0.400516,0.42018) -- (0.42018,0.42018) -- (0.42018,0.42635) --
(0.42635,0.42635) -- (0.42635,0.428008) -- (0.428008,0.428008);
\draw[thick,->-=0.5] (0.5,0.4375) -- (0.4375,0.4375) -- (0.4375,0.430664) --
(0.430664,0.430664);
\end{axis}
\end{tikzpicture}
\end{document}