Is available to use newgeometry command with nopagebreak?
\documentclass{article}
\usepackage[left=5cm,right=5cm,top=2.5cm,bottom=2cm]{geometry}
\usepackage{xcolor}
\usepackage{lipsum}
\begin{document}
\lipsum[1-15]
\newgeometry{left=5cm,right=5cm,top=2.5cm,bottom=2cm}
\textcolor{red}{\lipsum}
\restoregeometry
\end{document}
\newgeometrywithout a page break, but depending on your overall goal, other solutions might be found. What is your overall goal? – Steven B. Segletes Feb 06 '18 at 14:07