Can we have two pages with different number of columns?

Question

I want to write a paper where the first should consist of a single column and the next page should have 2 column format, is there any command available in Latex, please help

Answer 1

You can use \twocolumn for the second page (this command will start a new page):

\documentclass{article}
\usepackage{lipsum}% just to generate filler text

\begin{document}
\lipsum[1-5]
\twocolumn
\lipsum[1-5]
\end{document}

Another option would be to use the multicols environment from the multicol package (the environment doesn't start a new page by itself so you might need to use \newpage, or \clearpage at the end of the first page):

\documentclass{article}
\usepackage{multicol}
\usepackage{lipsum}

\begin{document}
\lipsum[1-5]
\begin{multicols}{2}
\lipsum[1-5]
\end{multicols}
\end{document}

In this case, you'll have to be careful with the use of floats since only page-wide floats (i.e., figure*, table*) can be used within the scope of the multicols environment.