2. Gridpapers

Grids can be made using LaTeX.
See the gridpapers at: https://ctan.org/pkg/gridpapers
See docs at: https://ctan.math.illinois.edu/macros/latex/contrib/gridpapers/gridpapers.pdf

2.1. Standard grids

This makes a standard grid.
 1\documentclass{article}
 2
 3\usepackage[
 4pattern=std,
 5majorcolor=gray,
 6minorcolor=black!10!white,
 7patternsize=0.5cm,
 8geometry={a4paper, portrait, hmargin=0.98cm, vmargin=2.33cm}]{gridpapers}
 9
10\begin{document}
11\thispagestyle{empty}
12~
13\end{document}

pdf

2.2. Dot grids

This makes a dot grid.
 1\documentclass{article}
 2
 3\usepackage[pattern=dot,
 4  patternsize=1cm,
 5  dotsize=1.7pt,
 6  fullpage,
 7  minorcolor=black!60!white,
 8  geometry={a4paper, margin=2cm}]{gridpapers}
 9
10\begin{document}
11\thispagestyle{empty}
12~
13\end{document}

pdf

2.3. Tri grids

This makes a triangular grid.
 1\documentclass{article}
 2
 3\usepackage[pattern=tri,
 4  patternsize=1cm,
 5  fullpage,
 6  minorcolor=black!30!white,
 7  geometry={a4paper, margin=2cm}]{gridpapers}
 8
 9\begin{document}
10\thispagestyle{empty}
11~
12\end{document}

pdf