Type LaTeX and the formula is drawn as you type, by MathJax, in your browser. Chemistry is written with mhchem: \ce{H2O}, \ce{A <=> B}.
Save the formula as an SVG that opens here again, copy it as a picture, or keep it in this browser. On draw.cheminfo.org and write.cheminfo.org, a formula added from here opens here again with a double click.
Write a LaTeX or mhchem formula and see it drawn as you type, save it as an SVG that opens again, learn the notation step by step, and practise it with graded exercises. The tool needs JavaScript, because the formulas are drawn in your browser.