This is one possible solution. It is quite possible that the question is a duplicate to this question.
\documentclass[12pt]{article}
\usepackage{fancyhdr}
\usepackage{lipsum}
\pagestyle{fancy}
\begin{document}
\tableofcontents
\clearpage
\section{blabla}
\lipsum{1}
\section{blablabla}
\lipsum{2}
\clearpage %from https://tex.stackexchange.com/questions/152589/how-to-add-a-line-to-the-table-of-contents-without-a-page-number
\addtocontents{toc}{%
\protect\contentsline{section}{Acknowledgments}{End Page}}
\section*{Acknowledgments}
\chead{}\rhead{Acknowledgments}\cfoot{End Page}
I'm grateful to an anonymous marmot sacrificing precious hibernation time for \TeX\ related questions.
\end{document}
For a given document class, there will very likely be much more elegant solutions.
\setcountersets a counter, i.e. a number. Depending on which document class and styles you use, there are different you use, there are different options. One of them is to use fancyhdr and to play with\cheadetc. But for people really to give you specific answers, you may want to specify the document classes and the relevant style files. – Nov 25 '17 at 03:15\AtEndDocument{\renewcommand{\thepage}{End Page}}. – Werner Nov 25 '17 at 06:36