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Ah, sure. As I think was already posted, https://homebrewery.naturalcrit.com/ is one option, of you want to look "official." DNDBeyond's homebrew creator sections is another if you use that, at least for certain things (monsters, items, etc).
You can also just use whatever though. Make a Google Doc, they share pretty well. Use Word (with some decent formatting) and convert to PDF for distribution. Use LaTeX - I think there are a few 5e or general RPG templates / packages (searching turned up https://www.overleaf.com/latex/templates/d-and-d-5e-latex-template/vmfdkjfhfynv and https://github.com/Krozark/RPG-LaTeX-Template for example).