How to place a `\draw` near the page number using `tikzpicture` environment

How about

\documentclass{article}
\usepackage[a4paper,margin=1in,footskip=0.25in]{geometry}

\usepackage{tikz}
\usepackage{fancyhdr}
\pagestyle{fancy}
\fancyhf{}
\rfoot{
    \begin{tikzpicture}[remember picture,overlay]
        \fill[black] (current page.south west) rectangle ++(\paperwidth,1.5cm)
        node[midway,align=center,font=\LARGE\bfseries,text=white] 
        (pageno-\number\value{page}) {\thepage}; % From https://tex.stackexchange.com/a/443744/152550
        \draw[white,ultra thick,line cap=round,line join=round] 
         ([xshift=-\paperwidth/4]pageno-\number\value{page}.south)
         --  ([xshift=-\paperwidth/4-7pt]pageno-\number\value{page}.center)
         -- ([xshift=-\paperwidth/4]pageno-\number\value{page}.north)
         ([xshift=\paperwidth/4]pageno-\number\value{page}.south)
         --  ([xshift=\paperwidth/4+7pt]pageno-\number\value{page}.center)
         -- ([xshift=\paperwidth/4]pageno-\number\value{page}.north);
    \end{tikzpicture}
}

\renewcommand{\headrulewidth}{0pt}
\renewcommand{\footrulewidth}{0pt}

\begin{document}

Example\newpage Another example

\end{document}

Here is a more versatile version. The arrows only appear when it makes sense, and by clicking on them you move to the previous or next page.

\documentclass{article}
\usepackage[a4paper,margin=1in,footskip=0.25in]{geometry}

\usepackage{tikz}
\usepackage{hyperref}
\usepackage{lastpage}
\usepackage{refcount}
\usepackage{fancyhdr}
\pagestyle{fancy}
\newsavebox{\manoooharrowL}
\newsavebox{\manoooharrowR}
\sbox\manoooharrowR{\begin{tikzpicture}
\draw[line width=1mm,white,line cap=round,line join=round] 
(0,0) -- (7pt,8pt) -- (0pt,16pt);
\end{tikzpicture}}
\sbox\manoooharrowL{\begin{tikzpicture}
\draw[line width=1mm,white,line cap=round,line join=round] 
(0,0) -- (-7pt,8pt) -- (0pt,16pt);
\end{tikzpicture}}
\fancyhf{}
\rfoot{
    \begin{tikzpicture}[remember picture,overlay]
        \fill[black] (current page.south west) rectangle ++(\paperwidth,1.5cm)
        node[midway,align=center,font=\LARGE\bfseries,text=white,xscale=1.5] 
        (pageno-\number\value{page}) 
        {\thepage}; % From https://tex.stackexchange.com/a/443744/152550
        \ifnum\value{page}<\getpagerefnumber{LastPage}
         \path ([xshift=\paperwidth/4]pageno-\number\value{page}) 
            node{\hyperlink{page.\the\numexpr\value{page}+1}{\usebox\manoooharrowR}};
        \fi
        \ifnum\value{page}>1
         \path ([xshift=-\paperwidth/4]pageno-\number\value{page}) 
            node{\hyperlink{page.\the\numexpr\value{page}-1}{\usebox\manoooharrowL}};
        \fi
    \end{tikzpicture}
}

\renewcommand{\headrulewidth}{0pt}
\renewcommand{\footrulewidth}{0pt}

\begin{document}

Example
\newpage 
Another example
\newpage 
Yet another example
\newpage 
Last page

\end{document}

Here is a very simple approach:

\documentclass{article}
\usepackage[a4paper,margin=1in,footskip=0.25in]{geometry}

\usepackage{tikz}
\usepackage{fancyhdr}
\pagestyle{fancy}
\fancyhf{}
\rfoot{
    \begin{tikzpicture}[remember picture,overlay]
        % From https://tex.stackexchange.com/a/443744/152550
        \fill[black] (current page.south west) rectangle ++(\paperwidth,1.5cm) 
        node[midway,align=center,font=\LARGE,text=white] (pgNum){\bfseries\thepage};
        % Left arrow
        \node[left of=pgNum, xshift=-3cm, scale=4, 
            path picture={\draw[line width=1mm, red] (.3,.3) -- (0,0) -- (.3,-.3);}] {};
        % Right arrow
        \node[right of=pgNum, xshift=3cm, scale=4, 
            path picture={\draw[line width=1mm, red] (-.3,-.3) -- (0,0) -- (-.3,.3);}] {};
    \end{tikzpicture}
}

\renewcommand{\headrulewidth}{0pt}
\renewcommand{\footrulewidth}{0pt}

\begin{document}

Example\newpage Another example

\end{document}