PdfLatex is a tool that converts Latex sources into PDF. This is specifically very important for researchers, as they use it to publish their findings. It could be installed very easily using Linux terminal, though this seems an annoying task on Windows. Installation commands are given below.

Install the TexLive base

apt-get install texlive-latex-base

On Windows, install MiKTeX or TeX Live with the native installer or a package manager such as winget. The apt-get commands only work in Linux or WSL.

Also install the recommended and extra fonts to avoid running into errors, when trying to use pdflatex on latex files with more fonts.

apt-get install texlive-fonts-recommended
apt-get install texlive-fonts-extra

Install the extra packages,

pdflatex